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Nursing Guide

Scholarly vs. Popular Resources

Keyword Searching

Subject Term Searching

How to Use Boolean Operators

Boolean operators are words such as and, or, and not that you use to combine search terms. An AND search says, find me articles that contain both of my search terms. Searches for cats AND dogs will retrieve articles that contain both the word "cats" and the word "dogs." If an article only contains the word "cats" but not the word "dogs", that article will not be retrieved. Venn diagram showing intersection of Cats and Dogs

Want to know more about creating effective searches using boolean operators? Follow the link below for information from UNC Asheville Libraries.

An OR search says, "find me anything that mentions either this term or that term." Searches for cats OR dogs will retrieve all the articles that contain the word "cats", the word "dogs", or both. You can also add more search terms into the mix, with the understanding that this will further expand your search. 

                                                                                 Venn diagram showing intersection of Cats or Dogs

A NOT search says, "Find me anything that mentions this term but not that one." Searches for cats NOT dogs will retrieve all the articles that contain the word "cats", but excludes from that list anything that uses the word "dogs." You have to be very careful when using this operator, as it will severely restrict your results and you may miss something important. An example of when to use NOT might be when you're looking for articles about dolphins (the animal) and you keep getting results with Dolphins (the Miami football team) You could do a search like, dolphins NOT football.

                                                                                        venn diagram showing intersection of Cats not Dogs

Improving Your Results

How can I improve my search results?

If you got too few results try one or more of these tips:

  • Use an OR with synonyms to broaden your search

  • Consult a thesaurus or index for more search terms

  • Reduce the number of concepts

  • Use more general terms

  • Use truncation to get variations or alternate spellings of your term

  • Use the broadest search possible (usually Keywords in most databases)

  • Check your spelling

  • Check to see if you used AND and OR properly

  • Check to see if you are using the best database for your topic

If you get too many results try one or more of these tips:

  • Use an AND to narrow your search

  • Use more precise terms

  • Use subject headings instead of Keywords

  • Consult a thesaurus or index for more narrower terms

  • Remove truncation

  • Search in a specific field, such as the Subject or Title field, instead of searching Keywords

  • Use limits such as language, years or document type.