As I have quite some emails (>13000) in gmail, searching more efficiently becomes a necessity. Fortunately gmail offers some advanced search syntax.
http://mail.google.com/support/bin/answer.py?hl=en&answer=7190
- Search emails with attachment
fmri meeting has:attachment - Search emails with attachment, and the attachment is a pdf file
fmri meeting filename:pdf - Search emails sent from John
fmri meeting from:john - Search emails sent to John
fmri meeting to:john - Search emails sent before 2009/08/01
fmri meeting before:2009/08/01 - Search emails sent after 2009/08/01
fmri meeting after:2009/08/01
