A few notes on searching the Bodliean collection
Firstly, the 'real' or printed names of the songs are quite often very different to the names
we use now (Lish young buy-a-broom was an exception!)
For example, instead of 'William Taylor', we find 'The Female Lieutanant'. Sovay, Sovay turns up as 'Sylvia's request and William's Denial'. Also, spelling has changed over the years. Jone's Ale (John's ale) has become Joan's Ale and now Joneses Ale.
Secondly, I usually have more success on searching by the second option, rather than the first(song title)

Thirdly, the Bodleian Indexes faithfully reproduce any spelling errors! Sometimes the song is there, but you can't find it.