Поттер как минимум видит книги в той ее части, которая скрывает вещи

Some of the items Harry has seen in the Room of Hidden Things
Broken and damaged furniture (mostly chairs, tables, & various cabinets haphazardly stacked), perhaps hidden to hide mishandled magic
Thousands and thousands of books (either in tottering piles or in bookcases)
The Half-Blood Prince's copy of Advanced Potion-Making