Not really sure in what context this would be said.
The english phrase "oh, there you are" could mean that you've been looking for someone and finally stumble across him and say that phrase.
Or it could be that someone has said "I've been asking and asking for someone to pass menthe scissors but no one is listening to me". To which the response is "oh, there you are [hands over scissors]".
I'm guessing the first is the right one but I want to check.
It is odd to me that you would use, "tiens" which is 2nd person, singular and "vous" which is 2nd person, plural in the same sentence. French seems to be rigid about agreement. I understand that "tiens" is an interjection, but I would expect it to match the number or the level of formality.