Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petriiv » peteriiv (Expand Search), petriiiv (Expand Search), petruiiv (Expand Search)
petrv » peterv (Expand Search), petriv (Expand Search), petruv (Expand Search)
petruuv » peteruuv (Expand Search), petriuuv (Expand Search), petruuuv (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 (((((petriov OR petruov) OR petriiv) OR petrv) OR petruuv) OR (petero OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((((petriov OR petruov) OR petriiv) OR petrv) OR petruuv) OR (petero OR petr)) o.s.*".