as myluck! said you need a clue to find a good cross-match - e.g. a first or surname
I had a search of the index using common first and surnames just to show what happens - and found three potential matches, all with the same references... no way to tell which is which, just that all of these brides appear on the same register page as Mathew and any one of them could have married him (and there could be other possibilities) :
Name: Mathew Geraghty
District: Roscommon
Event type: Marriage
Qtr / Year: Jan-Mar 1885
Volume : 3 / Page : 313
Name1: Kate Cormican
Name2: Sarah Carey
Name3: Jane Finneran
etc
Shane