Perhaps you should try some spelling variations:
petruov » petrov (Expand Search), petriuov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (Expand Search)
petrui » petriui (Expand Search), petruui (Expand Search), petroui (Expand Search), petri (Expand Search), petru (Expand Search)
petrooiu » petriooiu (Expand Search), petruooiu (Expand Search), petroooiu (Expand Search)
petroou » petrioou (Expand Search), petruoou (Expand Search), petrooou (Expand Search)
petriou » petriiou (Expand Search), petruiou (Expand Search), petroiou (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 (petruov OR (((petr OR petrui) OR (petrooiu OR (petroou OR petriou))) OR peter)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petruov OR (((petr OR petrui) OR (petrooiu OR (petroou OR petriou))) OR peter)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petruov OR (((petr OR petrui) OR (petrooiu OR (petroou OR petriou))) OR peter)) o.s.*.