How I can view CRM emails that have been sent from another module?

In our Contacts module we can see all IMAP/CRM emails for each contact.

In our Leads module,if there is the same email in there thats also in the Contacts module, we can see the IMAP emails, but not the CRM generated emails. How can we enable this? We need to see all CRM generated emails from within each module, NOT just the module that generated the CRM email.

Thanks