Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), peteriov (Expand Search), petriiov (Expand Search), petroiov (Expand Search)
peterov » petrov (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search), pentru (Expand Search), petri (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petrouo (Expand Search), pentruo (Expand Search), petrio (Expand Search), petro (Expand Search)
peteru » peter (Expand Search), peters (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 peterov) OR (((petr OR (petru OR peteru)) OR petruo) OR per)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR peterov) OR peterov) OR (((petr OR (petru OR peteru)) OR petruo) OR per)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR peterov) OR peterov) OR (((petr OR (petru OR peteru)) OR petruo) OR per)) o.s.*.