Listen to Koyal Niyan Boli online. Koyal Niyan Boli is a Bhojpuri language song and is sung by Raj Yadav. Koyal Niyan Boli, from the album Lasar Kutna Bhatar, was released in the year 2016. The duration of the song is 4:40. Download Bhojpuri songs online from JioSaavn.