There are many helpful search features in the library's PsycINFO database that will make your research easier. For example, you can begin a search like this, for peer-reviewed articles on obsessive compulsive disorder in females, ages 13 to 17.

You enter your search in the Search box (use quotation marks around phrases two words or longer). Then you can check the "Peer Reviewed" box to make sure you are getting academic, scholarly articles. You can also use the pull-down menus for "Age Groups" and "Population" to narrow your topic to specific groups who are being studied. It is best NOT to limit to only Full Text within the database, as you could miss potentially useful articles that may be available full text in other UMUC databases, but not in PsycINFO.
Here are the results for that search:

For example, your search so far is on obsessive compulsive disorder in females ages 13 to 17. If you wanted to narrow your topic further and see how cognitive behavioral therapy plays a role in this issue, click in the box next to "Cognitive Behavioral Therapy ". Then click 'Update". That subject phrase (or DE, which stands for descriptor) will automatically be added to your search. You will see that your results get smaller because you've narrowed your search:

Narrow Results by Subject is a great tool, but use it carefully! Don't just click on the links indiscriminately to get a lower number of search results. Simply clicking on the subject links one after another will lead to searches that don't really make sense. So, use "Subject" to narrow results to get ideas for alternative search terms and to carefully select keywords and phrases to add to your search.