Ok so im trying to think of what they r called but they are hollow, pillowy pyramid shaped cheese snacks very similar to bugles only the walls of the chips are very thin so u barely have to bite into them to break into the hollowness of them. They r very cheesy more so than Doritos and again they look like a pillowy pyramid.
I think you're thinking of the classic three dimensional Dorito, entitled Doritos 3D's. Despite being one of the best pyramid shaped chips, they're no longer available for purchase. Keep chipping away on your search for triangular snacks!