For getting pregnant we try between 13 to 18 days of our cycle for last five month. what should we do?

Gyn eval. : You want to be sure that, with an hsg x-ray - that the tubes are open, a spermanalysis is normal, and there is evidence of ovulation with an ovulation predictor kit - if desired. These will confirm available eggs, adequate and normal sperm, and uterus/tube anatomy - where sperm and egg meet. Sometimes medication or special procedures are needed , if nothing unusual is noted. Good luck.