As I understand it, enemas actually improve the peristalsis movement in the bowel and intestines. I personally have done an enema in the morning and had a bowel movement quite happily in the afternoon.
I usually take probiotics of some kind, acidophilus pills, when doing enemas. I read that some people open the capsules and actually add them to the enemas solution, so I tried that too. I can't say what difference it made but thought it couldn't hurt. I've been doing coffee or green tea retention enemas.
It might help to change your diet if you haven't already.
Enemas alone don't remove the mucus build up and plaque/stringy stuff on the inside of the colon, maybe you need more than enemas to start improving things.