Some databases provide full text while others only provide references to articles. Use the purple "Find it @ NU" button to locate full text access to the article.
If an article is not available at Northwestern University Library, you may request it via Interlibrary Loan (ILL). You will need to have an ILL account (see here for instructions on how to create one).
Google Scholar can quickly help you locate a variety of materials of a scholarly nature. If you configure the Library links section of Google Scholar, you will be able to use the Find it @ NU link in the Google Scholar results to quickly see if the Northwestern Library holds a copy of the source. In Google Scholar, go to Settings > Library links and select Northwestern University - Find it @ NU.