Perhaps you should try some spelling variations:
petr » petri (Expand Search), petro (Expand Search)
petru » petriu (Expand Search), petrou (Expand Search), pentru (Expand Search), petri (Expand Search)
petrou » petriou (Expand Search), petroou (Expand Search), petro (Expand Search), petrov (Expand Search), petrow (Expand Search)
petroi » petrioi (Expand Search), petrooi (Expand Search), petri (Expand Search), petro (Expand Search), petrov (Expand Search)
petrooi » petriooi (Expand Search), petroooi (Expand Search)
petroov » petrioov (Expand Search), petrooov (Expand Search), petrov (Expand Search)

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: fop (((peter OR (per OR (petr OR petru))) OR petrou) OR (petroi OR (petrooi OR petroov))) _. s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((peter OR (per OR (petr OR petru))) OR petrou) OR (petroi OR (petrooi OR petroov))) _. s.".
• Adding a wildcard symbol may retrieve word variants: fop (((peter OR (per OR (petr OR petru))) OR petrou) OR (petroi OR (petrooi OR petroov))) _. s.*.