Hi Uma,
Hope you are doing well, Your problem seems to be the most common among the job seekers.

I would like to suggest you to put more efforts on your resume and make it look good enough to get you call. the other thing is stop calling the employers because if they are really interested in your resume then they will definatley get back to you, No one would like to loose a candidate who is a perfect fit for there position. This i can say, as myself am an employer and i do the same. Add some more points to your resume and make it look different from other and interesting, however remember that your resume should only reflect genuine things which you have done.

Let me know if you need to discuss more. All the best for your future.

Regards,
SHANKAR.T