The Powershell one liner below will search the Message Tracking Log against every transport server in your Exchange Organization. Note that you may want to change the Select statement to include/remove which values you want to pull back into view (you can replace with the entire Select statement with FL to see every value available).
Get-TransportServer | Get-MessageTrackingLog -Sender:user@domain.com -Recipients user@domain.com -MessageSubject “another test” -Start 5/8/2014 | Sort Timestamp | Select TimeStamp, EventID, Source, MessageSubject, ClientIP, ClientHostname, ServerIP, ServerHostname
Ex-Shell 