Using either of the databases linked here, Academic Search Complete or Global Health, construct a beginning search following the patterns given in the examples below.
NOTE: Geography is difficult. You can try a city/state combination, but odds are against it working. You'll probably have to broaden the search geographically!
TOPIC: Childhood obesity among low-income communities in Alameda County
TOPIC: Asthma among school-age children in Richmond CA
TOPIC: Diabetes among Latinos in Los Angeles, CA
Run that initial search. Look closely at the relevant items retrieved, especially at the words/phrases labeled SUBJECTS. You are looking for relevant language describing each of the main ideas in your search.
Once you have found relevant language, edit your search so that you are searching in the SUBJECT field rather than the TITLE field.
In the examples above, our initial language was good for the 1st two examples. However, this is what the 3rd search ended up with. There was no consistent SUBJECT term for the idea of LATINO.
Once you have identified the basic issue or problem you want to work with you will need to find descriptions of attempts to tackle that problem! That's going to be harder.
For one thing, those kinds of article will not necessarily be addressing your issue in the same geographic area. Start searching using that same area, but keep in mind you may have to broaden it in some way. In my example, I could use the keyword URBAN, for example. If you find yourself retrieving a lot of material on other countries, but you are focusing on the United States, you can try adding a box with some states in it as you identify some specific geographic areas! This is where OR comes in handy.
Another thing you may have to do with this search is consider keywords or phrases that focus the search a certain direction, describe possible solutions, ideas that you read about in your first article ... that means using another search box!
Finally, you will want to add this very long phrase in an additional search box: