Borrowing words is pretty common. I went on an exchange to a small town in Québec when I was in high school. They borrowed English words to use in French. The only thing is that their use wasn't quite the same as English. For example, I was asked if a girl who was a good friend of mine was my "chum". I said yes, not knowing that they use it to mean girlfriend/boyfriend.

Good examples for English borrowing words are "nirvana" and "dharma". Both are hard to translate their meaning into English so we just go with the word itself.