ٱلَّذِينَ ضَلَّ سَعْيُهُمْ فِى ٱلْحَيَوٰةِ ٱلدُّنْيَا وَهُمْ يَحْسَبُونَ أَنَّهُمْ يُحْسِنُونَ صُنْعًا
Allazeena dalla sa'yuhum fil hayaatid dunyaa wa hum yahsaboona annahum yuhsinoona sun'aa
whose efforts in this world are misguided, even when they think they are doing good work?
those whose striving in the life of this world has gone astray, while they suppose they are doing good work.