Before you start searching for books or articles it's a good idea to take a minute to write down your topic or research question.
Example: The role of music in the civil rights era in the United States.
Next, identify the most important words and terms:
It is not necessary to include word like "the" or "in". In fact, those words can sometimes cause the search engine to return irrelevant results.
Then try to find any synonym or additional terms that may help narrow your topic: