Critic and study of the problem of prayer and some of the challenges

This writing, with attention to verse 60 of surah of Momen that in it, prayer is recommended and a positive answer is promised, with accurate analysis of prayer and regard for the Quran verses and tradition of the inerrant men, considers a challenge that it is, why doesn’t answer many of prayers?
The commentators said: condition of the materializatio n of a prayer is presence of expediency and purity of spirit. If a prayer isn’t accepted, it will because of absence one of two conditions or both of them. With attention to absoluteness of the verse in question, the author hasnt known sufficient answer of the commentators and hi has attained the more accurate answer himself.