Perhaps you should try some spelling variations:
petriv » petris (Expand Search), petrov (Expand Search), petroiv (Expand Search), periv (Expand Search)
petruo » petro (Expand Search), pentruo (Expand Search), petrouo (Expand Search), peruo (Expand Search)
petroi » petro (Expand Search), petrov (Expand Search), petrow (Expand Search), petrooi (Expand Search), peroi (Expand Search)
petru » pentru (Expand Search), petrou (Expand Search), peru (Expand Search)
petri » petroi (Expand Search), peri (Expand Search)
petr » petro (Expand Search), per (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 ((petriv OR peruiiv) OR ((petruo OR ((petri OR petroi) OR petru)) OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriv OR peruiiv) OR ((petruo OR ((petri OR petroi) OR petru)) OR (petr OR peter))) o.s.*".