Your search is too broad. Rather than using one general search term, combine two or more terms using AND.
A research question: What are the reasons for the high incidence of asthma among urban children?
Let's see how combining terms with AND works. The following searches were entered into Academic Search Complete, a database with millions of records.
When you enter just one term, you get thousands of results! They are all related to asthma in some general way, but do not necessarily discuss the incidence of asthma among urban children.
Joining two terms will give you fewer results. When you combine asthma and children, all hits will mention both asthma and children. They will be more relevant to your query and thus more useful to you.
Combining all three terms (asthma and children and urban) will give you even fewer results. Because all results will include these three terms, they will be closely related to your research question and will likely have the kind of information you need.
Your search is too narrow. Rather than using just one term, think of its synonyms. Once you come up with a few, combine them using OR.
When you enter Latinos as your only keyword, you will get results in which the word appears but will miss out on sources that use Hispanics instead. Using OR to combine these two terms (Latinos OR Hispanics) will ensure that you will get results that refer to either Latinos or Hispanics.
When you are searching an online library database, look at the search screen to see if there's an option to specify the date range. See an example below.
Because the time period has been set as the years 2000 through 2005, the list of results will include only sources that were published during this five-year period.
When you are searching an online library database, look at the search screen to see if there's a check-off box for Peer-reviewed (Scholarly) articles.
Because the box is checked off, all results will come from peer-reviewed (scholarly) publications.
Be aware that in some of the online library databases (e.g.JSTOR, Project Muse, and Sage Criminology) all articles come from peer-reviwed (scholarly) journals.