Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petriuiov » peteriuiov (Expand Search), petriiuiov (Expand Search), petruiuiov (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petruiui » peteruiui (Expand Search), petriuiui (Expand Search), petruuiui (Expand Search)
petruuuo » peteruuuo (Expand Search), petriuuuo (Expand Search), petruuuuo (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 petriuiov) OR (((petroi OR petruiui) OR (peteruo OR petruuuo)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR petriuiov) OR (((petroi OR petruiui) OR (peteruo OR petruuuo)) OR petr)) o.s.*".