I see that you have books missing from iBooks after updating to the latest version of iOS 11.1.1. I can certainly understand wanting to have access to your purchases, and I'd be happy to help.
Let's start by having you take a look at this article for steps to help regain access to those books again:
Redownload music, movies, TV shows, apps, and books from the iTunes Store, iBooks Store, and App Store
Take a look at the section titled "Redownload a book".
Thank you for using Apple Support Communities.
Have a great day!