I see a lot of people having trouble running this year. I did at first but I've tried to perfect it and I've been doing a lot better. Here's some tips that have helped me a lot.
1.
Know your RB. Don't toss to power backs and expect them to turn the corner. Hit up the gut with them, then MAYBE bounce a stretch if you feel confident. With speed backs you can usually take it off tackle well although pitches are high risk high reward. Don't be afraid to pound it with smaller backs, just don't get greedy. Cover that ball when contact approaches.
2.
Follow your blockers. This is very important. Don't try to cutback left and right while looking to take it outside when the play is designed inside the guard. If you have a lead blocker try sticking right behind him.
3.
Look for cutbacks. There's a fine line between over juking and looking for cutbacks. Be aware as soon as the ball is snapped. Look where the defense is committing. The next tip will help you with this. If you're designed to go off-tackle and there's a huge hole in the middle hit the highlight stick left to cutback and push forward. Just don't go running in circles looking for one.
Most important IMO
4.
Don't turbo off the line! I see so many people get the ball and just turbo forward into 3 offensive lineman's backs when a yard to the right there's a massive hole. You need to be patient (next tip). Look around when you snap. Read the defense. Look for holes. See where they are coming pre play. Look where your blocks set up. When you do see a legitimate spot to run in then turbo towards it.
5.
Use misdirection. Use counters to the weak side, cutbacks, etc. Don't always run to the strong side. Use some motion pre play. Look for man or zone coverage and try to exploit it. You don't always have to run to the side with the TE.
Lastly,
6.
Be patient! Not every play will be a 15 yard run plowing through people. How many times in real life do you see RB chipping away at a D then bust the big one? The defense will get worn down then you can hit it home. There's some games when you just won't be able to run. Stay calm and always be aware of your surroundings.
That's it pretty much. Once you get a good run game the opponent/cpu will pile the box and in return this will help your passing game also. Get the PA pass ready and start dominating. Hope this helps