"I know, but since the subject here is speaking, I wrote it that way. In fact, "Do you know Italian" is not what is said; "Do you speak Italian" is.
Thanks anyhow."
I think the translation is OK, but I would make one small change (except that I don't speak Italian). The speaker says s/he speaks VERY little Italian. The word "very" is missing. If it were English, I would say:
"Could you teach me Italian?
I only speak it a little."
Although "only" doesn't mean "very", it gives it the self-deprecatory feel that the original has.