Goc (Goch) (Gotch)/Buvalic; Vydra/Matejka

I am attempting to find the ancestors of my maternal grandparents and my husbands maternal and paternal grandparents. My Grandfather’s name was Peter Goc..this was changed to Goch after his arrival in the States. My grandmother was Maria (changed to Mary) Buvalic. I know that she was from the village?…town? of Bardejov in Slovakia. I do not know if my grandfather came from the same place. My husband, who is Czech, does not know where his grandfather, Vincent Vydra, or his grandmother, Mary Matejka lived in Czechoslovakia, although we know that Vydra seems to be a common name in Prague.

Any help will be appreciated.