how to find someone with a common name on facebook?

[Molly]

i just made a facebook because i need to contact my sister ASAP and my telephone died.
she has a very common name and its pages upon pages of people with the same name.
how can i narrow it down (to a city or something) to find her?
i live alone, my phone is dead so i cannot contact my parents.
there MUST be a way. there USED to be. they can't expect you to find anyone with only a name.
YES, Mido thank you!