Seek the time of Lailat-ul-Qadr in the last (ten nights), or he said: in the last nine (nights).

قَالَ رَسُولُ اللَّهِ ﷺ تَحَيَّنُوا لَيْلَةَ الْقَدْرِ فِي الْعَشْرِ الأَوَاخِرِ أَوْ قَالَ فِي التِّسْعِ الأَوَاخِرِ