How and where can I search for the a internal crm generated number ex: CRM:00013421

CRM auto generates a n internal like:  CRM:00013421

You will usually find it in the title or in notification subject line.

Examples: 

    - Your case CAS-13516-B8V6 has been closed. CRM:00013421

    - FW: support CRM:01080037

Any help is greatly appreciated.

Thanks