Like Searay said....don't get discouraged. Even if your graph lights up like a Christmas tree with fish doesn't always mean you have found fish that will bite. If that is the case then MOVE. No need fishing an area where they wont bite, an certainly don't fish an area where you see NOTHING on the graph. "Learn" your setup by pulling jigs towards the shallows to see where they begin bouncing (hitting bottom) so you know your depths and do this with several scenerios (different weight jigs, jigs with weights added, doubles, etc). It's the only way you will know what theyre doing behind your boat and is important when you see fish holding at a certain depth so you'll know how to rig for 'em. Remember, the fish are looking up....not down...so keep your jigs above the fish. Enjoy the learning curve and stay after 'em. You'll get it!
Health nuts are going to feel stupid someday, lying in hospitals dying of nothing.