If you do not know enough about your topic, you might want to get background information by utilizing encyclopedias, dictionaries and class textbooks which cover information in a comprehensive matter.
When searching for background information online go beyond Wikipedia; use authoritative encyclopedias and dictionaries that the UTEP Library subscribes to. One online databases that provides valuable background information is: Gale Virtual Reference Library.
You can't just throw your thesis into a database-they cannot parse whole sentences properly.
If you want to know if family income affects children's school attendance in the southwestern United States, you need to break that up.
Look at your results, what terms are popping up? You might not have phrased it like that, but maybe that is what it is called in the literature.