Perhaps you should try some spelling variations:
petrov » petro (Expand Search)
petruo » petro (Expand Search), pentruo (Expand Search), petrio (Expand Search)
pero » petro (Expand Search), per (Expand Search), pro (Expand Search)
petrui » petri (Expand Search), pentrui (Expand Search), petrii (Expand Search)
petero » peters (Expand Search), petro (Expand Search)
petruui » pentruui (Expand Search), petriui (Expand Search)
petru » pentru (Expand Search), petri (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 (petrov OR ((((petruo OR pero) OR (petrui OR petruui)) OR petero) OR (petru OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petrov OR ((((petruo OR pero) OR (petrui OR petruui)) OR petero) OR (petru OR peter))) o.s.*".