Sometimes, we all get frustrated doing research. In my observation, often the search terms used to find information may not be what matches academic literature terminology.
Many databases have a "Thesaurus" or "Subject" searching feature. I rely on those features when I can't find scholarly information.
Here is an example from ERIC:
If you're not sure how a topic is described in ERIC, look up your keywords in the ERIC thesaurus. Then add the descriptors (subject terms) you find to your search to make it more specific.
The advanced search in ERIC allows you to limit your search by date, educational level ( 3rd grade, secondary education, higher education, etc.) publication type ( dissertations/ theses, tests/questionaires, etc.) as well as a general publication type for primary research called reports--research.
