Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petriouov » peteriouov (Expand Search), petriiouov (Expand Search), petruiouov (Expand Search)
petriuo » peteriuo (Expand Search), petriiuo (Expand Search), petruiuo (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petriui » peteriui (Expand Search), petriiui (Expand Search), petruiui (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 peterov) OR petriouov) OR ((petriuo OR (petroi OR petriui)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR peterov) OR petriouov) OR ((petriuo OR (petroi OR petriui)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR peterov) OR petriouov) OR ((petriuo OR (petroi OR petriui)) OR petr)) o.s.*.