Perhaps you should try some spelling variations:
petra » petro (Expand Search), petre (Expand Search), petera (Expand Search), petroa (Expand Search)
petr » peter (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petroi (Expand Search)
petroi » peteroi (Expand Search), petrooi (Expand Search), petro (Expand Search), petrov (Expand Search), petrow (Expand Search)
petroov » peteroov (Expand Search), petrooov (Expand Search), petrov (Expand Search)
petru » peteru (Expand Search), petrou (Expand Search), pentru (Expand Search)
petero » peter (Expand Search), peters (Expand Search), petro (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 ((((petra OR per) OR (petr OR petero)) o) OR ((((petri OR petroi) OR petroov) OR petru) _)). s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petra OR per) OR (petr OR petero)) o) OR ((((petri OR petroi) OR petroov) OR petru) _)). s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petra OR per) OR (petr OR petero)) o) OR ((((petri OR petroi) OR petroov) OR petru) _)). s.*.