Perhaps you should try some spelling variations:
petr » peter (Expand Search), petro (Expand Search), per (Expand Search)
petru » peteru (Expand Search), petrou (Expand Search), peru (Expand Search), pentru (Expand Search)
petrou » peterou (Expand Search), petroou (Expand Search), perou (Expand Search), petro (Expand Search), petrov (Expand Search)
petrow » peterow (Expand Search), petroow (Expand Search), perow (Expand Search), petro (Expand Search), petrov (Expand Search), petrowna (Expand Search)
petri » peteri (Expand Search), petroi (Expand Search), peri (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 petru) OR (petrou OR (petrow OR peterou))) OR petri) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petr OR petru) OR (petrou OR (petrow OR peterou))) OR petri) o.s.*".