Perhaps you should try some spelling variations:
petruuov » petrov (Expand Search), peteruuov (Expand Search), petruuuov (Expand Search), petrouuov (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petroi » peteroi (Expand Search), petruoi (Expand Search), petrooi (Expand Search)
petrouo » peterouo (Expand Search), petruouo (Expand Search), petroouo (Expand Search)
petruuo » peteruuo (Expand Search), petruuuo (Expand Search), petrouuo (Expand Search)
petr » peter (Expand Search), petru (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 (petruuov OR (((petri OR petroi) OR ((petrouo OR petruuo) OR peteruo)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petruuov OR (((petri OR petroi) OR ((petrouo OR petruuo) OR peteruo)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petruuov OR (((petri OR petroi) OR ((petrouo OR petruuo) OR peteruo)) OR petr)) o.s.*.