1. "Thank you for your reply. I like it very much. "
2. "Thank you very much for coming back. I am very touched. "
3. "Your return is so polite that I am embarrassed."
4. "I didn't expect you to prepare a gift in return. Really touching. "
5. "Your reply is very practical, and I will make good use of it."
In short, express gratitude, avoid being too modest or too enthusiastic, and keep a proper balance to express sincere gratitude.