Is it good to write a Critical report on my own published research work? After 1.5 years of PhD I found some flaws in my PhD published work. The flaws are minor in nature, and an improved work can not be consider novel enough to be publish again. 
How can I report those minor flaws and make them available to public?  
Few of them came in my notice via email conversation from other researchers. If I can publish a report by some way, then how to give reference the private email conversation?
This is one of the issues that are solved by preprint archives. If your work was on arXiv, you would just post an updated version there, and not worry about the published version, because readers usually go to arXiv. Probably your work is not on arXiv, or you would not ask the question. Then you might enquire whether you are allowed to post it there, and/or consider doing it for your subsequent works.