Using Boolean Operators (AND, OR, and NOT) with your keywords will help you narrow or expand your results.
The highlighted middle section represents the use of AND. Searching for poverty AND addiction will give you results with both words present. Therefore, your results are fewer.
Using OR between similar keywords will give you results that include both words. Therefore, your results are greater. A search for teenagers OR adolescents will retrieve either or both terms.
The NOT operator gives you results from only one of your words. Therefore, your results are fewer. Searching for addiction NOT alcohol will eliminate alcohol from the results.
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