+create an index file /tmp/mymail/2010-2011/mymail.db
+
+And
+
+.P
+.nf
+.B mymail --db-pattern '\.db$' --db-root /tmp/mymail \e
+.B \ \ \ \ \ \ \ --output /tmp/mymail.mbox \e
+.B \ \ \ \ \ \ \ --search 'p bob.something' \e
+.B \ \ \ \ \ \ \ --search '!s spam' \e
+.B \ \ \ \ \ \ \ --search 'month'
+
+.fi
+will search in all the database files *.db located (recursively) in
+/tmp/mymail, for all the mails having "bob.something" as sender or
+recipient, without "spam" in the subject, received over the last 31
+days, and create an mbox file /tmp/mymail/mbox.