Perhaps you should try some spelling variations:
petriow » petrow (Expand Search), peteriow (Expand Search), petriiow (Expand Search), petruiow (Expand Search)
petrov » petro (Expand Search), peterov (Expand Search), petriov (Expand Search), petruov (Expand Search)
petroi » petri (Expand Search), petro (Expand Search), petrow (Expand Search), peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petrivw » peterivw (Expand Search), petriivw (Expand Search), petruivw (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (Expand Search)

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petriow OR petrov) OR petrivw) o) OR ((petroi OR petr) _)). s.~".
• Adding a wildcard symbol may retrieve word variants: fop ((((petriow OR petrov) OR petrivw) o) OR ((petroi OR petr) _)). s.*.