Unable to Conceive. What the problem is?

I was diagonesd with PCOD earlier this year in Februrary. My periods had been irregular. The timming was irregular but the Flow was ok. I reduced my weight from 78 kgs to 70 kgs. After taking medicines my PCOD finished. Even though my Periods got regular my Flow seems to be affected. And periods have become more painful. In Ultrasound it is showing my Endometrium is thin. I am trying to conceive but not able to. Both me and my Husband do not have any other Medical condition like BP, SUGAR, THIROID etc. We are not able to understand why we are nit able to conceive. It is getting  very depressing that even after eating so many medicines and trying for last 2 months nothing is happening. MAM CAN YOU PLEASE GUIDE US AS TO WHAT THE PROBLEM IS ???