Search messages with partial sender addresses

I am trying to search my inbox for messages originating from a particular domain (my work domain).  When I put in the character string (upenn), I should be seeing mail from all senders with that characters string in any part of the email address.  Instead, in only see the fraction that have that character string beginning right after the @.  This is not the expected behavior. 

If I start typing in a colleague’s email address, I will see every email from that person.  Could eMclient actually be matching only from the beginning of the string?  That needs to be fixed if that is the case.  If I type in “.edu”, I want to see every email showing up from a university address.

Paul

I think I figured it out.  On a whim, I typed a * in front of the character string, and suddenly I was looking at all of the emails I wanted.  This is a more general specification, but it does differ from the way Thunderbird did things.