This short video created by Gabriele Library at Immaculata University can help you understand how to create search statements and combine search strategies.
The use of Boolean Operators is an effective search strategy. Using the words AND or NOT will limit your search results, providing you with fewer hits. Using the word OR will expand your search and provide a greater number of results.
To see how this works, visit The Boolean Machine.
Truncation can expand your search results to include information or concepts that you may otherwise overlook. By using a "wildcard" in your search, you may find several variations of the same word or concept.
For an overview of truncation, visit Owens Library's Truncation page.