Limit (type "?" for help): ?
     RETURN          all messages
     ~b EXPR         messages which contain EXPR in the message body
     ~B EXPR         messages which contain EXPR in the whole message
     ~c USER         messages carbon-copied to USER
     ~C EXPR         message is either to: or cc: EXPR
     ~D              deleted messages
     ~d [MIN]-[MAX]  messages with date-sent in a Date range
     ~e EXPR         message which contains EXPR in the Sender field
     ~F              flagged messages
     ~f USER         messages originating from USER
     ~g              cryptographically signed messages
     ~G              cryptographically encrypted messages
     ~h EXPR         messages which contain EXPR in the message header
     ~i ID           message which match ID in the Message-ID field
     ~k              message contains PGP key material
     ~L EXPR         message is either originated or received by EXPR
     ~l              message is addressed to a known mailing list
     ~m [MIN]-[MAX]  message in the range MIN to MAX *)
     ~n [MIN]-[MAX]  messages with a score in the range MIN to MAX *)
     ~N              new messages
     ~O              old messages
     ~p              message is addressed to you (consults $alternates)
     ~P              message is from you (consults $alternates)
     ~Q              messages which have been replied to
     ~r [MIN]-[MAX]  messages with date-received in a Date range *)
     ~R              read messages
     ~s SUBJECT      messages having SUBJECT in the Subject field.
     ~t USER         messages addressed to USER
     ~T              tagged messages
     ~U              unread messages
     ~v              message is part of a collapsed thread.
     ~x EXPR         messages which contain EXPR in the `References' field
     ~X [MIN]-[MAX]  messages with MIN to MAX attachments *)
     ~y EXPR         messages which contain EXPR in the `X-Label' field
     ~z [MIN]-[MAX]  messages with a size in the range MIN to MAX *)
     ~=              duplicated messages (see $duplicate_threads)
     ~$              unreferenced messages (requires threaded view)

Arguments are regexps.
Arguments are simple strings if you use = instead of ~ as search operator.

*) The forms <[MAX], >[MIN], [MIN]- and -[MAX] are allowed, too

Logical AND is performed by specifying more than one criterion.
!  -- logical NOT operator
|  -- logical OR operator
() -- logical grouping operator

Example:  !(~t mutt|~c mutt) ~f elkins