Hey!
Yes.. and there's an only way for that...
practicing scales.... The average practice range of the singer should be three octaves. If you don't have three octaves of practice range, it means the instrument itself lacks development. Development is establiched thought working on scales.
The scales will teach the vocal cords what to do on every given pitch so that, if you're practicing on a regular basis, the cord will eventually remember what to do on their own when singing songs.