Though it may look simple at first glance, Hathitrust is a very complex system. It's not always easy to understand. The best place to get answers to many of your questions is through their very excellent Help pages.
If you are a frequent user of HathiTrust resources, it's also a good idea to follow them on Twitter, where they often post research tips and announcements at @hathitrust.
If you have any questions not answered in the pages of this guide, please contact the librarians using the "Ask Us!" links on the library's website, come in and visit us at the Reference Desk, or contact us through this link.
Are you having problems with accessing items in HathiTrust? Please contact the library so we can help solve the problem.
Also, remember that items can also be obtained through our Inter Library Loan service.