Firstly, avoid adding water..cook in ghee or butter. If you really want to thicken a gravy, add corn flour slurry or mashed aloo in it.
Saute onions before grinding so when you make gravy they leave less water. Add roasted Besan or ground coconut.
Boil veg separately, then add only the veg tothe fried items,not water. cook on high flame,stiring constantly. As suggested before ,better cook in open pan than closed ones. Then u can dry water easily.cooking on slow flame leave too much water from veg.