RDL and SLDL work amazing. High rep low rep. Kill it all. That's just what has really been a significant difference with mine. Rep schemes don't matter if your getting a mind muscle connection. Technically progressive resistance is your best bet on lagging body parts.
Another thing I learned from Dallas Mccarver is when your doing lying hamstring curls curl your feet up towards your shins instead of away. A lot of people try to do too much weight by pointing the toes away from the body but this involves a lot of lower back by doing this.
Point those toes upward and really squeeze the shit out of the positive portion of the rep. Dig into those fibers and make them hurt.