Problems running the ball...

I play with the 9ers and Ravens mostly, and i find myself being hit in the backfield more times than not. Even on 3 man lines sometimes the DT just comes clean and rails me. I try to play clock control, and my inability to get out of the backfield hampers that.

My question is... what are some good plays that have more success than the current loss of yards plays I try? Ive tried running goal line on a 3-4 and get swallowed up.. try PA from the same formations and I get nailed even when I have numbers.

Thanks.