deadbeef-f00d-f00d-deadbeef isn't a valid UUID v4
Aside from missing a grouping in the middle, you need the version and variant bits, ie:
XXXXXXXX-XXXX-4XXX-VXXX-XXXXXXXXXXXX
where V is 8, 9, A, or B
searching for deadbeef-f00d-400d-a00d-deadbeef does return the expected matches