Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petruiiv » peteruiiv (Expand Search), petriuiiv (Expand Search), petruuiiv (Expand Search)
petriu » peteriu (Expand Search), petriiu (Expand Search), petruiu (Expand Search)
petrouuuuo » peterouuuuo (Expand Search), petriouuuuo (Expand Search), petruouuuuo (Expand Search)
petriuiuo » peteriuiuo (Expand Search), petriiuiuo (Expand Search), petruiuiuo (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 petruiiv) OR peterv) OR ((petriu OR (petrouuuuo OR petriuiuo)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR petruiiv) OR peterv) OR ((petriu OR (petrouuuuo OR petriuiuo)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR petruiiv) OR peterv) OR ((petriu OR (petrouuuuo OR petriuiuo)) OR petr)) o.s.*.