When I fishing in hydrilla I have been successful when I flip soft plastic into holes in hydrilla.

What are some other techniques that might help me fish better in thicker stuff.

Run a rattle trap type/crank bait parallel  to the hydrilla line. If you are fishing from a boat that is. If you have a heavy rod with #50 braid or higher fish a hollow body frog through the pockets or the lightly covered areas and hold on!!.

Soft body swim bait rigged weedless with a belly weighted screw lock hook. I use a gambler big ez with 1/4oz hook. Reel it slowly over the top and let fall into the holes. You can also buzz it on the surface

Traps if their chasing, flip the center with a 1 ounce weight.