i just refill my coolant about 2 weeks ago.... and now its gone, trying to check everything but no leak.. should i take to service?

 

It is more likely leaking than being burn by the engine. If the car is blowing white smoke from the exhaust after its warmed up you are burning coolant. Do you smell the sweet smell of coolant in the engine compartment? Look for blue residue anywhere around the overflow tank.

 

Check exhaust for vapor or a sweet smell.

Check for leaks, especially the small tube from the overflow to the radiator near the radiator cap.

Check the oil fill hole for signs of water vapor or a "milkshake" looking oil.

 

I agree with what they say ^^ , it could be various things but if you don't see any out side leakage then it night be internal which would mean your engine seals.