Perhaps you should try some spelling variations:
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petrov » peterov (Expand Search), petruov (Expand Search), petroov (Expand Search), petro (Expand Search)
petrooi » peterooi (Expand Search), petruooi (Expand Search), petroooi (Expand Search)
petriooi » peteriooi (Expand Search), petruiooi (Expand Search), petroiooi (Expand Search)
peteroi » peterdi (Expand Search)

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

• Performing a fuzzy search may retrieve terms with similar spellings: fop ((petr OR peterou) OR (((petri OR petrov) OR peteroi) OR (petrooi OR petriooi))) _. s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petr OR peterou) OR (((petri OR petrov) OR peteroi) OR (petrooi OR petriooi))) _. s.*".