Shaykhul Hadith Maulana Muhammad Zakariyya Rahimullah has compiled a book in the virtues of good deeds by the name فضائل الأعمال. Many objections are made on this book regarding it’s authenticity. Some people say that, all the Hadith mentioned in this book are weak.
A scholar from Nepal has done the complete research regarding this book in Arabic by the name;
“تحقيق المقال في تخريج أحاديث فضائل الأعمال”
which is a very good source to understand the levels of all the Hadith mentioned in Fadhaail Al A’mal by Shaykhul Hadith Zakariyya Rahimahullah.