First, organize your research topic into concepts. Concepts are typically nouns or noun phrases.
Using a databases's Advanced Search, enter each concept and its synonyms into a separate search line.
Use quotation marks around phrases, these are typically noun phrases that you would find a definition of in a dictionary.
Use * for truncation.
Limit to peer-reviewed articles if necessary.
Limit by date if necessary.
Too many or too few results?
Find an article that looks interesting?