Perhaps you should try some spelling variations:
petrov » peterov (Expand Search), petriov (Expand Search), petruov (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petruuov » peteruuov (Expand Search), petriuuov (Expand Search), petruuuov (Expand Search)
petruuv » peteruuv (Expand Search), petriuuv (Expand Search), petruuuv (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petruuo (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 (((petrov OR ((petruov OR petruuov) OR peteruov)) OR petruuv) OR (petruo OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petrov OR ((petruov OR petruuov) OR peteruov)) OR petruuv) OR (petruo OR petr)) o.s.*".