Can we supplicate after salah?
The Sunnah is to supplicate during prayer and before final salutations (tasleem).
After prayer we recite prescribed remembrances of Allah such as “Allahuma antas-Salam wa minkas-salam…”
Then we glorify Allah (tasbeeh) and dhikr. The Scholars say that supplicating after prayer is a deviation from the Sunnah, so just (stick to) dhikr (prescribed remembrances) and tasbeeh.