Stomach ache is one of the most common pains that the youth is facing nowadays! The cure is very simple, but the lack of medical knowledge to follow that. Drinking plenty of water, avoiding junk & spicy foods can be a good treatment. In worst cases, doctor's advice must be taken at any cost. But apart from this, Qur'an will be very much helpful to reduce the pain. I've shared an article that contains Dua which cures stomach pain. Do follow that if the pain still persists.