Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), petruiov (Expand Search), petroiov (Expand Search), periov (Expand Search)
petriiv » petruiiv (Expand Search), petroiiv (Expand Search), periiv (Expand Search)
petroiiuv » petruoiiuv (Expand Search), petrooiiuv (Expand Search), peroiiuv (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search), peri (Expand Search)
petriuo » petruiuo (Expand Search), petroiuo (Expand Search), periuo (Expand Search)
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)

Try widening your search to All Fields.

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 petriiv) OR petroiiuv) OR ((petri OR petriuo) OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR petriiv) OR petroiiuv) OR ((petri OR petriuo) OR (petr OR peter))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR petriiv) OR petroiiuv) OR ((petri OR petriuo) OR (petr OR peter))) o.s.*.