Hi Suryamshu, congrats for your first car. And as far as car running great and looks good be happy. For revealing the bad part now, based on tasjeel finding. When car is overheated single or multiple timing then engine head has a gasket that gets bad (shrink) and mix the coolant and oil inside engine. Engine can actually die slow death coz of this mixing and loose tremendous power. What i assume that previous owner must have had cracked radiator coz of which car overheated and that's why he changed the radiator and fixed the head gasket by opening engine head (which is not a normal job and it is quite expensive). I also assume here, that being expensive job he must have gotten it done in sub standard garage to save money and hence sold the car. If it would have been done at good garage or dealership its almost impossible to make out if engine head is opened or not.
Another assumption, is engine head also get opened for changing the timing belt and your previous owner must have changed that at 80k kms, if i am not wrong. Call Habtoor and check at how many km you need to change the timing belt, if its 80k then may be this assumption is quiet right. If they say at 100k or after 100k then previous (bad) assumption must be right.
Also open the hood of your car and see right under the bonnet the mesh or cardboard that sits right under bonnet metal is disfigured, loose and look worn out or burnt (majorly)???? Then car has been severely overheated and my first assumption is quite right.
Don't feel bad, as its your first car and everyone have their sour story for the first time. What you can do now, is to get it car checked at good garage like dynatrade, technical resources and let them diagnose it for 200 AED that how good or bad head gasket job is done. And how is the current overall condition of your car and if it need some further attention. More than likely you will be changing the timing belt in coming few thousand kms, so at that time you can get that job done at good garage for approx 3000 AED or at dealership for 5000 AED and enjoy the car with peace of mind.
Have fun and drive safe.