Please don't resort to enemas or anal douching to solve this problem. You just need more fiber in your diet. Your diet is pretty bad, I'm not going to tip toe around that. You eat only processed food, no fiber, no fruit, no veggies, no whole grains. Of course you're going to have wipe your butt 50 times and still not get it clean. There's no fiber cleaning your gut while so you're constantly excreting shit. Your colon is probably caked with old feces because it's so sticky that it never completely moves out. Sorry if that's gross but the quality of your shit actually tells you a lot about what's going on inside you.
The term "incomplete bowel movement" is specific. It means that you keep having to return to the toilet because it's not done coming out. That's not your problem. Your problem is that you have sticky, damp stool from all the refined food you're eating, with no fiber to break it up or scrub your bowels out.
Just eat more fiber for god's sake. It's not that hard. Steam some broccoli for 5 minutes, put salt and pepper on it. Eat it all. There, instant fiber. Or eat sauerkraut as was suggested. Cabbage is fiber. Actually any raw veggies are going to give you fiber, or brown rice.
It takes less work to steam some veggies than shove an enema up your ass. If you don't start eating more fiber you'll be at higher risk for colon cancer because all that old shit stuck in there is not meant to stay there.