The police in UAE are not there to help Indian people get their passports returned... and I suspect it would be incredibly dangerous to start complaining to them; your only reason to be there is to work, cheaply and shut up. You are a second class citizen and it’s unbelievably naive to start sticking your head above your station. You’ll be telling them they should start a union next!
Western expats might be second class citizens in the UAE, with some luck. As a worker from India in the UAE, you are far treated far below a second class citizen, sadly.