Do you have your CDL? If not i can almost guarantee that is why you aren't getting any responses on you apps. If you have it then just be persistent and the work will come. But if not then I would be doing everything possible to get one. There are too many lineschool grads applying for the same jobs who have gone the extra mile to get every cert. and license they made need in order to get hired. Applying isn't gonna be enough if you don't have certs and experience