Don't get frustrated. "Винни-Пух" is not an easy read! There's a lot of wordplay as far as I can remember, and a lot of self-made words. Find something intended for younger children to build your vocabularly and gain confidence (but not fairy tales, they are pretty hard too because of a certain style and many obscure and dialect words).

I've PMed you a couple of easier stories. Try them. They are not too easy, but I think you'll be able to understand them just fine.