Library Texts - Drilling Down and Adding
In any view, clicking on the title of a sub-folder will navigate down into that sub-folder.

In the example above, we have navigated down into the chapter "1. Structure and function of skin" and no longer see the full chapter list of the entire text.
Articles can appear at any point within the hierarchy of topics. To add an article to a chapter or sub-chapter, you use the "Add Item" drop down.

You'll notice that when you are in the Library, the "Add Item" drop down only includes Articles and Texts.

