Perhaps you should try some spelling variations:
petrouuv » petrov (Expand Search), peterouuv (Expand Search), petriouuv (Expand Search), petruouuv (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petruuo (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petruui » peteruui (Expand Search), petriuui (Expand Search), petruuui (Expand Search)
petruio » peteruio (Expand Search), petriuio (Expand Search), petruuio (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 ((petrouuv OR peteruv) OR (((petruo OR (petroi OR petruui)) OR petruio) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petrouuv OR peteruv) OR (((petruo OR (petroi OR petruui)) OR petruio) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petrouuv OR peteruv) OR (((petruo OR (petroi OR petruui)) OR petruio) OR petr)) o.s.*.