Please help...still got stuck with it

i really dunno how to find the song anywhere...so anyone help me pleaseeee

its a latin song (i Guess) since its a ost (ending song) of a uhm latin series (about three sisters and the main characters is a nurse) the lyrics that stuck in my mind only this words "numero Uno"

its sweet, slow and lovely song. i really love it and really wish to hear it again, so please help........

seem like its the hardest song i ever try to find....hehehe...no luck with this one...