Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petrv » peterv (Expand Search), petruv (Expand Search), petrov (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petriu » peteriu (Expand Search), petruiu (Expand Search), petroiu (Expand Search)
petruiu » peteruiu (Expand Search), petruuiu (Expand Search), petrouiu (Expand Search)
petr » peter (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 ((petriov OR (petrv OR peterv)) OR (((petri OR petero) OR (petriu OR petruiu)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR (petrv OR peterv)) OR (((petri OR petero) OR (petriu OR petruiu)) OR petr)) o.s.*".