Which food oils, or oily foods, give a good stimulus to move your bowels?

Fiber: In general, the best natural way to "move bowels" is to eat foods with high fiber content. Fiber is material that can't be broken down by our gastrointestinal system and move things along. Oil and oily foods are absorbed by the gut, unless there is some sort of enzyme deficiency, so they aren't effective for what you're suggesting. Very oily foul smelling stools are termed steatorrhea.