My company runs sendmail on RH Linux and I cannot figure out how to view headers from a message that came in.

If I watch the mail logs, I can see the messages coming in. If I run grep "from=<zang" /var/log/maillog, It pulls up something like:

May 17 08:43:02 mail sendmail[2854]: q4HCWV09002929: to=<zang.....>, delay=00:00:00, etc..
I tried to grep on the q4HCWV09002929 but it says No such file or directory. I want to see the from field because I am trouble shooting something and I need to see when a certain address emails me.