Ask questions about your topic.
Who/What (e.g. what population is involved; what is the age group; who benefits...don't try to answer all of these only the one that makes the most sense for your topic).
When (e.g. is your topic current; does it need to have a date limitation, such as the last six years)
Where (i.e. university setting; United States; regional; lower socio-economic status neighborhoods, etc.)
Why (why this topic? why this question? Who benefits from the results?)
Trying to answer the questions will assist in identifying keywords and will help you to think more about your research question (and why you have selected your topic).