Enchanted Books

I was in a mineshaft and found a chest with Enchanted books and they dont have a enchant on them.

I expected to find a enchanted book with enchants.
I thought I should have got a enchanted book with a enchant.

I found a bunch of books with no enchants on them.

Steps to Reproduce:
1. Find mineshaft and explore it
2. Find a chest with books in it
3. The discover books have no enchants on them