After every qaṣr prayer, it is recommended that a traveller says thirty times: ‘subḥānal lāhi wal ḥamdu lillāhi wa lā ilāha illal lāhu wal lāhu akbar’.[1] Although it is recommended to recite this dhikr after every obligatory prayer as well, in this case [i.e. for a traveller after every qaṣr prayer], it is recommended even more, and it is better to say it sixty times after ẓuhr, ʿaṣr, and ʿishāʾ prayers.
[1] For the translation of this phrase, see the fifth section of ‘Translation of prayers’ after