Skip to Main Content

Ready Reference Guide for LibChat


Have a Research Question but don't know where to Start Searching?


Creating a research question is a very difficult step in the research process. Now, it is time to discuss how a research question is translated into an optimized keyword search sting for databases. 

One very important thing to keep in mind

Library databases are Not Google. When we search within library databases, we need to tell the database to search for exact words (most library databases only search for exact word matches). We also need to give the database instructions on how to search for those exact words/keywords by defining the relationship between the exact words/keywords. Google has many complicated algorithms that perform these functions automatically. Library databases lack these sophisticated algorithms. We do this through the use of Boolean Operators and proper exact word/keyword identification. 

Boolean Operators 

Boolean operators are words that are included in a search to define the relationship between keywords. Google does this automatically, but we need to tell library databases what the relationship is between words. The Boolean operators are: AND, OR, NOT. For example, searching "Dog AND Cat" will retrieve articles that are about both dogs and cats. Searching "Dog OR Cat" will retrieve articles that are only about dogs, only about cats, or are about both dogs and cats. Searching with NOT can be useful for eliminating unintentional meanings of words. For example, the word "bat" can refer to an animal or to baseball. If I was searching for information about the animal "bat", I can eliminate articles about baseball by using the NOT operator. An example search would look like: "bat NOT baseball'. This technique can be useful for eliminating articles that aren't on your topic. 

Define your Keywords

Now that we understand Boolean operators, we need to isolate keywords from our research question. Isolating keywords will help remove unneeded words and help the database narrow down on precise results. Use PICO to help identify your keywords. PICO is explained in-depth here. For example, if your research question was "Does industrialization effect the ecosystems of Brazilian rainforests?", do not type the whole question into the search box. Use the PICO method to identify the keywords.

  • P - Brazilian Rainforests/Rainforests in Brazil
  • I - Industrialization
  • C - N/A
  • O - Ecosystems

Do not include prepositions or plurals within keywords. For example, you can remove the "in" within "Rainforests in Brazil". You can also remove the plural of "rainforests" and "ecosystems". "Rainforest, Brazil, Brazilian, Industrialization, and Ecosystem" can be used as our keywords. 

Apply Boolean Operators

Now that we have our keywords, it is time to apply Boolean Operators to our search string. All the major concepts identified by PICO need to be present within our target articles. We would use the Boolean Operator AND to define this relationship. AND tells the database that we require both words that AND connects to be present in the article. A sample search string would be "Rainforest AND Brazil AND Industrialization AND Ecosystem". We must use a Boolean Operator between each word to define its relationship to the next word. 

If we were interested in using keywords that are synonyms for the same concept, we would use the OR operator. For example, we identified in our above PICO format that Brazil and Brazilian are synonyms to each other. We would not use AND to connect these words because they are synonyms to each other. The presence of either word within an article is sufficient for finding an article related to Brazil. We do not need both words to be present in the article. Thus, we would use the OR operator. An example keyword search would look like: Rainforest AND (Brazil OR Brazilian) AND (industrialization OR urbanization) AND ecosystem. The parentheses group like terms/synonyms together, and it helps keep an organized search. 

HERE are the search results after using this search string in a database called Science Direct. 

If we were interested in removing a false lead or an unintentional meaning of a word, we would use NOT to remove that meaning. This operator is not commonly used during searches. Its use only applies for when we want to remove a meaning that is completely unrelated to our topic. For example, the word "seal" has two different meanings. It can mean a seal (the aquatic animal) or seal (an official stamp). NOT would be used to eliminate a meaning from the word. For example, "seal NOT stamp". 

Confused? Need more of an explanation? Read this page HERE

Using Limiters

There are 1,121 results for the above search string in Science Direct. That's a lot of articles. It's time to apply some filters to help narrow down the results. We don't want too many articles because it's burdensome. We also don't want too few articles because that may inhibit our research process. One popular limiter to help shrink the amount of results is the "date" filter. Many professors or assignments may require you to only use recent research, which translates to research performed in the last 5 or 10 years. Other popular filters include "language", "article type" (i.e. book chapter, encyclopedia, review article, research article, clinical trial, and etc.), "peer-reviewed", and "full text". We do not recommend applying the full-text filter, because full text articles that are not available in a database can be requested for free through SHU's ILL (Inter-Library Loan). Limiters/Filters differ between databases. Some limiters/filters may be present in one database but not in another. 

After applying the "date" and "article type" filter to the example search, the search results shrank to 243 articles. Click HERE to see the results. 

Those results are now a group of targeted research articles that specifically address the research question. Remember, searching is an iterative process. You will not get perfect search results on your first try. Try rephrasing keywords or adding synonyms to the search string based on the articles you're seeing in your search results. If you are having issues, refer to the next page in the guide. 


  • Library databases are NOT Google. Library databases need specific searching instructions. 
  • Use PICO to help define your keywords. Do not use prepositions or plurals as keywords. 
  • Use Boolean Operators to define the relationship between your keywords:
    • AND - both keywords must be present in the article. This operator is used for connecting keywords of different concepts. 
    • OR - one or both keywords must be present in the article. This operator is used for connecting keywords that are synonyms or conceptually related to each other.
    • NOT - do not include articles with that keyword. This operator is used for removing an unintentional meaning of a keyword. 
  • Use the database's limiters/filters to help specify/narrow down the search results.