Yeah, definitely start taking Betaine HCL and digestive enzymes with each meal
Those two supplements are the best thing that ever happened to my health, they have done wonders for my energy, constipation, weight
The undigested bits in your stool make me really think that enzymes and Betaine are the right suggestion, I used to have large undigested bits come out before I started supplementing. It's rather unsettling to see a corn kernel come out looking exactly the same as it did when it was eaten