Using a "concept map" can help you narrow your topic, while also helping develop a research strategy - this just means coming up with multiple ways you can go about your search, rather than be frustrated by limited results.
Here is an example of a concept map that explores different keywords for the various aspects of the topic. Notice that the four corners give you some guidance on what kind of keywords to think about.
Worksheet from Indiana University Bloomington / University of Virginia
https://libraries.indiana.edu/handouts-worksheets-activities-information-literacy
