First you have to find a source of this infestation. There is a place in your home, harden, farm, warehouse which you have completely forgotten. Weevil bugs mostly hide there and that is the place where they reproduce. Conduct a proper search for that place. It is mostly well hidden and moist, which is perfect for them. Also, the source of weevils is mostly near a place where you can see the biggest amount of them. You will probably hear them eating a wood, flour or some other nutrition. Good advice is to use stethoscope to find them.