In admin I see "App_name object" but not actual object name

In admin I see "App_name object" but not actual object name

So, I learning django by this
http://mherman.org/blog/2012/12/30/django-basics/ tutorial and I have one
problem.
I added couple books to database but in admin site I see only "App_name
object". In my case I see only list of words "Books object", "Books
object", "Books object" when actually I should see "War and Peace", "Brave
New World", "To Kill a Mockingbird".
So, do you know what's wrong with my app?
Thank you ;)