Hmmm.. this one is a little tricky...
But I would say Kahin performs the same function as "I suppose..." or like an aren't you/are you?
For eg this sentence
कहीं आप गर्म मिज़ाज के तो नहीं? - I hope you are not a hot tempered? Are you?
or I suppose you are not a hot tempered person?
My try