I used to be plagued by moles at a home I used to own. Over the years I managed to trap about 50 of the little varmints. I used one of these traps;
https://www.wildlifecontrolsupplies...MI07KynvGM2QIVg5R-Ch1QrwE6EAQYAiABEgK4sPD_BwE
A few observations.
The fresh soil mound you see is the debris from a fresh tunnel being made. When the mole digs, the soil has to go somewhere. When the soil is pushed up the branch tunnel the mole can go back to digging the main tunnel. What you are looking for when you set a trap is the main tunnel, not the branch tunnel where the soil debris exits. A little probing with a long screwdriver will locate the main tunnel.
The absence of fresh mounds of soil does not mean no moles. It means that the food supply in the existing tunnels is enough for the moles.
Place the trap in the main tunnel. Dig a hole that is centered over the main tunnel. The hole should be only large enough to fit the trap. If the tunnel collapses while digging it, use a different location. Otherwise the mole is as likely to go around the trap as through it.
The trap should be placed in such a way that a mole using the tunnel will pass though the trap and trigger the trap.
You can increase the likelihood of the trap being triggered by placing a small mound of moist soil topped with a tin can lid under the trap's trigger. The slightest activity in the tunnel near the trap will now trigger the trap.
Be sure to remove the trap safety catch. I don't know how many times I have found the trap upended but not triggered.
Place a bucket securely over the trap. The trap doesn't know the difference between a mole, your dog or your neighbor's kid.
This approach works. When you pull a dead mole carcass from the jaws of the trap and "airmole" it into the woods you have proof of success.
Good luck
John