Perhaps you should try some spelling variations:
petruov » peteruov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petrouv » peterouv (Expand Search), petruouv (Expand Search), petroouv (Expand Search)
petrouo » peterouo (Expand Search), petruouo (Expand Search), petroouo (Expand Search)
petroouo » peteroouo (Expand Search), petruoouo (Expand Search), petrooouo (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 (((petruov OR petruov) OR petrouv) OR (((petrouo OR petroouo) OR (petri OR per)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruov OR petruov) OR petrouv) OR (((petrouo OR petroouo) OR (petri OR per)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruov OR petruov) OR petrouv) OR (((petrouo OR petroouo) OR (petri OR per)) OR petr)) o.s.*.