You could be searching I and lo and come up with nothing more.
As a nonsense vocable it still is used in pop songs 'Hi lily, hi lily, hi lo. (Tom Jones)
And occurs in old ballads. Earl Brand Child's first version has a chorus line 'Ay lally, o lilly lally' which I have heard sung as
'Hey lilly o lilly hi-lo'
The Cruel brother contains refrains such as
oh lily oh, Lily o, sweet hi o.
With the high and the lily oh.