How to get rid of foul smelling gas.

I have been suffering from foul-smelling gas for the last three years. No particular food causes it. Any food consumed causes a smell. Sometimes I feel gas being stuck in different parts of my body and it releases very slowly. The main problem is smell. I don't have any other digestive issues other thn occasionally contipation. Charcoal tablets, probiotic meds , hingwastik churna didn't work well. Please tell me how to fix this smell as early as possible. If it is fermentation of food problem in the digestive area how to get rid of this( I am getting married in December) . PS - SIBO and H. pylori reports are negative, Ultrasound is fine and endoscopy is normal. No celiac and lactose allergy. Any other test required?