east texas bass fishing problems

I live on a small lake, about 90 acres and this year becuase of the
lack of rain the lake level is down about 4 feet. I dont know if it is
because of this but i cannot seem to catch a fish. I have tried
everything on it from, cranks, spinners, top water, worms, flukes, and
virtually everything in my tackle bow, i've even stooped low enough to
try a minnow and bobber... Now i cannot figure out what to through at
these bass, nothing is working. The conditions outside have been
actually pretty nice, not to hot sunny days and little to no wind,
which makes me think to use a topwater. The wierd thing is this lake
has always been great fishing i have pulled out a 13.56 pound bass and
1.89 pound black crappiie.... what im tryin to get at is i am in a
slump and i cant catch anything, if anyone has any advice or if you
have been through this yourself please help me out....any info in
appreciated. thanks