Taking some chlorophyll can help to hide the poop smell if you're bowel incontinent as the chlorophyll helps to mask the smell of the poop before it leaves your body so that when you poop in the diaper it won't smell or smell as bad.
You can also apply baby powder to the diaper before putting the diaper on which can help to mask the smell of poop or wear cologne or perfume while out in public and the people will smell the cologne or perfume instead of the poop.