Perhaps you should try some spelling variations:
petrooov » petrov (Expand Search), peterooov (Expand Search), petriooov (Expand Search), petroooov (Expand Search)
petroov » peteroov (Expand Search), petrioov (Expand Search), petrooov (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petrou » peterou (Expand Search), petriou (Expand Search), petroou (Expand Search)
petroou » peteroou (Expand Search), petrioou (Expand Search), petrooou (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 ((petroov OR petrooov) OR (((petru OR peterdi) OR (petrou OR petroou)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petroov OR petrooov) OR (((petru OR peterdi) OR (petrou OR petroou)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petroov OR petrooov) OR (((petru OR peterdi) OR (petrou OR petroou)) OR petr)) o.s.*.