Here is the all 21 book of Dr. Zakir Naik in bangla language is here. I found it from here.
It is an wonderful book about quran and other religious book by zakir naik . Here it is proved that quran is the god’s ( Allah) word.
Here is another beautiful book on islam and comparative religion by Zakir Naik.
This is another good book written by Zakir Naik.
This is the slide show of zakir naik’s lecture.
Are there any similarities between Hinduism and Islam is exist? Here it is answered. You can download it from below.