There is an option when you create a ticket in which phase you have found the ticket. See attachment.
I would like to generate a report using Found in phase to see if the tickets are found after the product is released (Post_release) or when we are in developing stage.(Feature Verification)
The answer depends on what form you want the report to be. A list or a chart or other? On the surface what would seem to work would be to create a filter and then use the filter on a pie chart on a dashboard. This would allow you to get relative view of where issues are found in the product phase and the user can drill down. I assume the Found in field is available in the list to chart against.