Perhaps you should try some spelling variations:
petrio » petris (Expand Search), petro (Expand Search), petruio (Expand Search), petroio (Expand Search), perio (Expand Search)
petrov » petro (Expand Search), petruov (Expand Search), petroov (Expand Search), perov (Expand Search)
petruuv » petruuuv (Expand Search), petrouuv (Expand Search), peruuv (Expand Search)
petrouuv » petruouuv (Expand Search), petroouuv (Expand Search), perouuv (Expand Search)
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)
petri » petrui (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 ((petruuv OR petrouuv) OR ((petrio OR petrov) OR ((petr OR petri) OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruuv OR petrouuv) OR ((petrio OR petrov) OR ((petr OR petri) OR peter))) o.s.*".