You may use what information you have to search for the article in SLUth, the main search on the library homepage that searches almost every item in the library, print or electronic. You may need to refine your search using limiting tools on the left side of your screen to find the correct item or save time.
If you have a complete article citation or at least know the name of the journal in which the article appeared and the title (or author) of the specific article, you may want to start by searching the E-Journal Portal for the journal. This is how you'll know which database(s) include the journal in which your article appeared, and then you can search by title or author within that content.
As always, if you have any questions or need help finding a specific article, you are encouraged to ask a librarian!