+\fBf <regexp>\fR (from) selects mails whose leading line From, or
+fields From:, or Reply-To: matches the regexp.
+.TP
+\fBt <regexp>\fR (to) selects mails whose field To:, Cc:, or Bcc: matches the regexp.
+.TP
+\fBp <regexp>\fR (participant) selects mails whose leading line From,
+or fields From:, Reply-To:, To:, Cc:, or Bcc: matches the regexp.
+.TP
+\fBs <regexp>\fR (subject) selects mails whose field Subject: matches the regexp.
+.TP
+\fBd <regexp>\fR (date) selects mails whose field Date: matches the regexp.
+.TP
+\fBb <regexp>\fR (body) selects mails whose body matches the
+regexp. Evaluatin such a condition requires to read the original
+mboxes completely, which can be slow. However, header conditions are
+checked first to read the bodies only for mails which fulfill them
+entirely.
+.TP
+\fB8h\fR selects mails received during the last 8 hours.