Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), petruiov (Expand Search), petroiov (Expand Search), periov (Expand Search)
petero » peters (Expand Search), petro (Expand Search)
petriuuo » petruiuuo (Expand Search), petroiuuo (Expand Search), periuuo (Expand Search)
petrouiuuo » petruouiuuo (Expand Search), petroouiuuo (Expand Search), perouiuuo (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 (petriov OR (((petriuuo OR petrouiuuo) OR petero) OR ((petr OR petri) OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petriov OR (((petriuuo OR petrouiuuo) OR petero) OR ((petr OR petri) OR peter))) o.s.*".