Perhaps you should try some spelling variations:
petriv » petris (Expand Search), petroiv (Expand Search), periv (Expand Search)
petrov » petro (Expand Search), petroov (Expand Search), perov (Expand Search)
petru » pentru (Expand Search), petrou (Expand Search), peru (Expand Search)
petrou » petro (Expand Search), petrow (Expand Search), petroou (Expand Search), perou (Expand Search)
petri » petroi (Expand Search), peri (Expand Search)
petroiiv » petrooiiv (Expand Search), peroiiv (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 petri) OR petroiiv) OR petrov) OR ((petru OR petrou) OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petriv OR petri) OR petroiiv) OR petrov) OR ((petru OR petrou) OR (petr OR peter))) o.s.*".