Perhaps you should try some spelling variations:
peterov » petrov (Expand Search)
petroov » petrov (Expand Search), peteroov (Expand Search), petrioov (Expand Search), petrooov (Expand Search)
petroi » petri (Expand Search), petro (Expand Search), petrov (Expand Search), peteroi (Expand Search), petrioi (Expand Search), petrooi (Expand Search)
petru » pentru (Expand Search), petri (Expand Search), peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petrio » petri (Expand Search), petris (Expand Search), petro (Expand Search), peterio (Expand Search), petriio (Expand Search), petroio (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (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 ((peterov OR petroov) OR (((petroi OR petru) OR (petrio OR petrio)) OR (petr OR per))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((peterov OR petroov) OR (((petroi OR petru) OR (petrio OR petrio)) OR (petr OR per))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((peterov OR petroov) OR (((petroi OR petru) OR (petrio OR petrio)) OR (petr OR per))) o.s.*.