Complex sentence: Many few know that Maulana Shabbir Ali Thanvi served as secretary to Hazrat Thanvi and was his most closest associate of Hazrat Thanvi in his private and official matters and used to meet Mr. Jinnah during Pakistan movement on behalf of Hazrat Thanvi when there was a need be.
Split into simpler sentences: Many few know that Maulana Shabbir Ali Thanvi served as secretary to Hazrat Thanvi and was most closest associate of Hazrat Thanvi in his private and official matters. It was Maulana Shabbir Ali Sahib Thanvi who used to meet Mr. Jinnah during Pakistan movement on behalf of Hazrat Thanvi when there was a need be.