Perhaps you should try some spelling variations:
petrio » petri (Expand Search), petris (Expand Search), petro (Expand Search), petriio (Expand Search), petruio (Expand Search), petroio (Expand Search)
petriov » petriv (Expand Search), petrisv (Expand Search), petrov (Expand Search), petriiov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petrv » petrov (Expand Search), petri (Expand Search), petru (Expand Search), petriv (Expand Search), petruv (Expand Search)
petruio » petriuio (Expand Search), petruuio (Expand Search), petrouio (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (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 (((petrio OR petruio) OR petriov) OR (petrv OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petrio OR petruio) OR petriov) OR (petrv OR (petr OR peter))) o.s.*".