Another coolant leakage? Or something else?

What is your question?

There seems too be another leakage somewhere. I've already replaced the coolant expansion tank and the valves but I still have to put in coolant during hot weathers. The thermostat doesnt go past the half mark, so it may not be overheating. The new problem I have is that a liquid is leaking and burning which is causing the car to smoke up. The smoke is a light coloured smoke and it smells like something is burning. The smoke is coming from above the engine and it only happens sometimes, it doesn't continuously smoke up. The leakage has stained my driveway as well when I have the car sitting there. Could that stain be from oil? Just so I know what's leaking.