Do you have a college degree? That's probably the single quickest yes-no box for screening.
If you don't have one, you obviously got your current job without one, but on paper, you're going to frequently lose out to other candidates that do have one. That's just how it is.
The other thing is how many jobs you've applied for. 20+ jobs to a recruiter in a relatively short time looks like you're applying for anything under the sun instead of thoughtfully/selectively applying for roles that are a great fit.
Lastly, have someone unbiased look at your resume. You might think it looks ok but there's gotta be -some- reason for that many denials.