returns not running

[teedoff]

Just had the pool installed last fall and as of yet been unable to use. the pool stayed fairly dirty waiting on the deck to be poured. Now I'm trying to clean the pool that is very dirty and it seems the returns arent working properly. I call them "jets" but its the spouts under water that returns the water to the pool. Anyway when I try to set up the vacuum I can sometimes turn the pump off then on again to get the hose primed and hooked up. Only to lose suction after a few minutes of vacuuming. Then I have to repeat the process. Its very aggrevating and I'm not so sure something is'nt wrong here. I've backwashed a couple times and the water got clear, but if I keep having to backwash the water is running low. By low I mean its already below halfway mark of the skimmer. Again, to make this simple, I know little about pool maintainance, but I know the water is not running through the filter like it should. please can anyone give some advice??..btw I think the pump is a Hayward with a sand filter.