A more colloquial way to say this in English would be "what you don't know won't hurt you". But you can also translate it the way you did.

Hmmm, I'm thinking that's close, but maybe it would be something more like this, "If your eye doesn't see, then your heart won't be bothered." Used mdbg for translating this, so correct me if I'm wrong.

Out of Sight, Out of Mind.