You may need to have an exterminator come in and professionally spray the grounds and perhaps fog the attic areas within the house. This will remove most of the insects so you can regain control of them. No one treatment will remove all of them at one time. The goal is to use what is called integrated pest management. This is where you control the environment in which they are living and make it hostile for them to survive. Then follow up if need be with chemicals. Controlling the environment is as simple as cutting the lawn, removing storage, keeping area dry by perhaps pitching soil away from home etc.