Perhaps you should try some spelling variations:
petrouov » petrov (Expand Search), peterouov (Expand Search), petriouov (Expand Search), petruouov (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petroiv » peteroiv (Expand Search), petrioiv (Expand Search), petruoiv (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petruui (Expand Search)
petrio » peterio (Expand Search), petriio (Expand Search), petruio (Expand Search)
petroiio » peteroiio (Expand Search), petrioiio (Expand Search), petruoiio (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 (((petruov OR petrouov) OR petroiv) OR ((petrui OR (petrio OR petroiio)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruov OR petrouov) OR petroiv) OR ((petrui OR (petrio OR petroiio)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruov OR petrouov) OR petroiv) OR ((petrui OR (petrio OR petroiio)) OR petr)) o.s.*.