Listen to Oi Mahamanab online. Oi Mahamanab is a Bengali language song and is sung by Manoj Murali Nair and Rabindranath Tagore. Oi Mahamanab, from the album Belasesher Gaan, was released in the year 2016. The duration of the song is 1:13. Download Bengali songs online from JioSaavn.