that 1st link to the Voice of America page is the right page. On the left side there is aCollections section with - "MORE" option . that was how I got to the other page, I went into More and Checked the box for " American Libraries" that is what brought up the other titles for me.
Also if you just pic a subject, like Amercian Indians of North America and type it into the big "meta search bar at the top of the original page it will take you to all kinds of books documents, audio video on just that topic. The meta search library is massive and some of the titles you can see on the site and use on the site, others you actually have to apply to borrow from the library