Thank you, same to you
is appropriate if someone is taking a vacation at the same time as you are. It is, in English, polite, understood to be appreciative, and adequate as a response. To say more is not common in English.
However cultures vary, and if your culture supports that style, then
Thank you! Now that you've wished me well, I'm sure it will be awesome!
is fine. But the same to you, very common (and expected) in English would turn it into a mouthful.
If someone is not taking a vacation at the same time, clearly same to you is not useful. If you want to express gratitude beyond thank you!, you might say,
*Thank you. I hope so, too."
Usually, in English (American, in any case), we don't say Happy vacations. We say, have a nice/good/great vacation, or enjoy your vacation!