Hi,

You can't. Soundpools are pre-recorded loops of instruments and voices. You can only change the tone up or down. Try singing a line of a song and recording it but skip a few words. What you want to do would be like somehow magically having the program insert the missing words using your voice. Can't be done.

If you want special chords and notes, then you have to play them yourself. For that you have instruments and a keyboard and recording to MIDI or you can record the output or sound of an external instrument.

See also the answer to your previous question.