In order to say "thank you", I can say 谢谢 or 谢谢你. What if I want to be more specific and say "thank you for (something)"?
As an example, suppose I was invited for dinner at someone's place, and I want to write a card to the host on which I say "thank you for inviting me for dinner", how would I say that? Or how would I say "thank you for the gift"?