The Prophet ﷺ said, "Whoever seeks it, let him seek it in the last ten nights."
عن النبي ﷺ قال: من كان ملتمسها، فليلتمسها في العشر الأواخر.
Muslim narrated it in the Book of Fasting (1165: 210) from Muhammad bin Muthanna, who said, Muhammad bin Jafar narrated to us, who said, Shubah narrated to us, from Jabalah, who said, I heard Ibn Umar say (then he mentioned the hadith).