There’s actually a few ways to wholesomely understand it.
The girls would actually start by saying (brought in same gemara) bachur sa na einecha – raise your eyes, and don’t look at a girl for her exterior. Sheker hachein vhevel hayofi. So how then did the girls themselves say ein haisha ela lyofi?
Anyhow here’s in very short – I’ll be happy to elaborate on any.