* Bientôt (French) means "soon" or "shortly."
* Grazie di (Italian) means "thank you for" or "thanks for."
While grammatically correct in their respective languages, combining them doesn't make a coherent phrase in English. It's essentially a mix of "soon" and "thank you for" - not something you would naturally say in English.
To understand the meaning in context, you'd need more information:
* What's the full sentence or phrase? Are there other words around "bientôt Grazie di"?
* What's the situation? Who is saying this to whom and about what?
Knowing more would help determine the intended meaning and allow for a proper English translation.