Thick Cover..ugh!
Just like here in Wa. State on the West Side? Ya, thats what I have to hunt in at times, myself. Sometimes I get lucky and find nice open fields.
A few things about the thick woods, is that they can be 50 yards away, or 5 miles away. Its hard to tell. I usually try and find signs of trails, footprints, scat. I spend lots of time scouting an area, looking for signs.
If it gets too thick, then I try and call them out to a small area, open field, or even a trail. Here in Wa. State, we have lots of logging roads, and I have called them out of the thick stuff onto these roads.
Sneak in, be quite, take your time, find a place to call them out into the open. When you do take cover, try and setup that you can swing your rifle around and cover as much area as you can. They can come from many directions.
If you can't find them, then try locating them at night, and come back to that area latter during the day, and try again. Here in Wa. State, and I am sure elsewhere, they have many hunting grounds. Farms, houses, parks,,etc. Them come down at night, and even during the day and hunt these areas, then in the morning, they head back out into the woods. Far, far away.
They are like ghost out here. I've been luck to catch a few. But in the thick stuff, they can see and smell you way before we can get a glimpse of them.
Good luck
Lastcat