fishy odor bowel

what can I do about the smell of my bowel. I take 2 shower a day but yet i still smell bad. I do not understand this. I can not smell it be other can. They make a joke about fish or I over hear them talking about me. Now my bowel move ment does have a fishy ordor I can smell every time One goes to the bathroom. So how this smell is coming out of my body even when I am not having a bowel movement. What can I do.