Perhaps you should try some spelling variations:
petrov » petro (Expand Search), peterov (Expand Search), petroov (Expand Search), perov (Expand Search)
petruov » pentruov (Expand Search), peteruov (Expand Search), petrouov (Expand Search), peruov (Expand Search)
petru » pentru (Expand Search), peteru (Expand Search), petrou (Expand Search), peru (Expand Search)
petrouv » peterouv (Expand Search), petroouv (Expand Search), perouv (Expand Search)
petr » peter (Expand Search), petro (Expand Search), per (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 ((petruov OR petrov) OR ((petru OR petrouv) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruov OR petrov) OR ((petru OR petrouv) OR (petr OR petri))) o.s.*".