C: A284 SEARCH TEXT "string not in mailbox"
  S: * ESEARCH (TAG "A284")
  S: A284 OK SEARCH completed
  C: A285 SEARCH CHARSET UTF-8 TEXT {12}
  S: + Ready for literal text
  C: отпуск
  S: * ESEARCH (TAG "A285") ALL 43
  S: A285 OK SEARCH completed