I've looked around for an answer in the FAQs, and I haven't seen one, so I'm asking here.  I've had some trouble with searching by phone number, because some numbers are listed as (xxx) yyy-zzzz, others are listed as xxx-yyy-zzzz, and some are xxx yyy-zzzz, and some are in other formats, with spaces included sometimes.  The search function doesn't seem to know that they're all the same number, so I have to run several searches, and that's just cumbersome.

Is there, for lack of a better term, a style guide that defines how a phone number should be entered?  Am I missing something obvious about my searches?

Thanks in advance!