Original: She read The Dutch Twins by Lucy Fitch Perkins, and became a frequent visitor to the library, though she still had difficulty finding the types of books she most wanted to read.
Simplified: It wasn't until she was in third grade that she found enjoyment from books, when she started reading The Dutch Twins by Lucy Fitch Perkins. Thereafter, she was a frequent visitor to the library, though she rarely found the books she most wanted to read — those about children like herself.