Translation:Hello, do you have a room for two people?
Here's my take on this. I'm not a Czech native speaker, but it's my understanding that nějaký is often used simply to mean "a/an," though it can also have the meaning that you suggest. On the English side, I'd say that "Do you have a room..." is much more likely to be used than "Do you have some kind of room..." -- maybe especially so here, since the sentence specifies the kind of room -- "for two people" -- that's of interest. (Just one person's opinion...)