Hi Vero,
Thanks for the workflow. I'm on Day One with Alfred, so excuse me if I'm being dense. I had a mail that I somehow disappeared today. It was nowhere to be found - then via a web search I discovered that if you have the mail app on top you can search thorough Time Machine - and I found the mail I lost.
Given this recent and very frustrating episode, I wanted to check out how Alfred could help. So I downloaded your WFl and tried by typing "emfrom krzysztof" (and yes I'm spelling that right!) - the workflow result bit displays but no result was returned, but I can see an email from this guy staring me in the face. It seems to work okay using the other two keywords though. What am I missing?