can't find the big bass

[Makitcnt4u]

On the lake I fish I have fished cliffs, points, the old streambed, the main channel, flats. I have been fishing this lake for 7 years and I have never seen any weeds, lillypads,duckweed,seaweed. All of the places I fish have plenty of cover and I also find places with plenty of structure on the bottom with my fishfinder. All I ever catch is small(1-2 pound bass). I've had the occasional 4 pound bass but I can't find any fish that are bigger. :'( ??? At all the tournaments they have 10-12 pound fish. What other landmarks should I fish? What other lures should I get to attract the big bass? ??? What should I do? Please Help me!