Listen to Koyel Kyon Gaaye online. Koyel Kyon Gaaye is a Hindi language song and is sung by Mohammed Rafi and Lata Mangeshkar. Koyel Kyon Gaaye, from the album Aap Aye Bahar Ayee, was released in the year 1971. The duration of the song is 6:57. Download Hindi songs online from JioSaavn.