Search results are already limited to the "Full Text" option, however the Odones would have likely turned that limiter off so they could find more resources. CINAHL Plus with Full Text is the database used by professional nurses across the United States. Click on Subjects to search CINAHL subject headings which is the vocabularly used predominantly in the Nursing field.
Start by searching by keyword. Then click on relevant subjects that will be visible on the left hand side of the results page.
Pubmed (also known as Medline) is the current version of Index Medicus, the resource Michaela Odone used with a microfilm reader to find articles related to different topics (such as the one she found on Polish rats). This database is provided by the National Institute of Health (its Library the Odones most often visited in Washington, D.C.) and the Pubmed interface is available to anyone who has Web access, without any need for any subscription.
LexisNexis Academic is a newspapers, business, and legal resources database. The Odones would use LexisNexis to get the latest news about any new research found in related health areas as well as perhaps to look up particular company information that may contain the type of oils that they are seeking. They would also may seek particular legal information or court cases in case any legal issues would come up.
To access databases off campus, you enter your W number as your username (begin with a CAPITAL W). Your password is: the first two letters of your first name, the first two letters of your last name, and the last FOUR digits of your W Number. To learn more, take this tutorial (you will need Flash):
If you still have problems getting in, take this tutorial: