Answered By: Melissa Johnson
Last Updated: Sep 17, 2021     Views: 0

Boolean operators can help improve the quality and quantity of your search results. They must be typed in ALL CAPS to function correctly.

AND - Use AND to narrow down your search results. Each search result will contain all of the terms that you searched.

  • Ex: climate change AND drones

OR - Use OR to expand your search results. Each result will contain at least one of the terms you searched.

  • Ex: climate change OR global warming
  • If you use OR in a search query with AND, be sure to nest terms using OR inside parentheses.
    • Ex: United States AND (climate change OR global warming)

NOT - Use NOT to exclude terms from your results. 

  • Ex: plasma NOT blood


Learn more about Boolean operators and additional search syntax from EBSCO:

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