Could you please give an example of the usage of this question?
For example when a robber forces you to show him where you hide your jewels.
Or maybe a doctor asking you in which body part you feel the pain, ''Kde máte ty bolesti?''.
I don't get this sentence, is it used frequently in common talk?
Well, when you want to ask where does someone have something, it is quite natural.
It' s like the " j" sounds like an "e", continuing "kde"?