Listen to Koyal Bolen Kyun online. Koyal Bolen Kyun is a Hindi language song and is sung by Bappi Lahiri and Kavita Krishnamurthy. Koyal Bolen Kyun, from the album Janata Ki Adalat, was released in the year 1994. The duration of the song is 5:13. Download Hindi songs online from JioSaavn.