There are several translations depends on the situation. I would say: 何か飲むものがほしいですか or 何か飲みたいですか。(like "do you want something to drink?" or "do you want to drink something.") 何か飲み物を買いたいですか。(like "do you buy something to drink.") would like to ~ / want to ~ = ~ (し)たい (Ex. "want to drink" = 飲みたい) something to drink = 何か飲むもの or 飲みもの I hope this was helpful.

@Eric.A, thank you for your addition, I totally forgot about that. @Abbs, Eric's phrase is "nani ka onomimono wa ikaga desu ka?".

Well Eric san, unfortunately i can't read nor right Japanese. I'll try to find a way to know how that's said. Domo arigatou though :3

In addition to Ryoko san's explanation, if you were a waiter, you could also say "何かお飲み物はいかがですか。". You wouldn't say that to your family or friends though. Good luck with your study!

If you want any help with English, feel free to ask me, i'm new to this website so i still have nobody to help me with Japanese. If you'd like we can help each other out. :3