Perhaps you should try some spelling variations:
petruuov » petrov (Expand Search), peteruuov (Expand Search), petriuuov (Expand Search), petruuuov (Expand Search)
petruiov » petrov (Expand Search), peteruiov (Expand Search), petriuiov (Expand Search), petruuiov (Expand Search)
petruv » peteruv (Expand Search), petriuv (Expand Search), petruuv (Expand Search)
petruuo » peteruuo (Expand Search), petriuuo (Expand Search), petruuuo (Expand Search)
petruui » peteruui (Expand Search), petriuui (Expand Search), petruuui (Expand Search)
petrioi » peterioi (Expand Search), petriioi (Expand Search), petruioi (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 (((petruuov OR petruiov) OR petruv) OR ((petruuo OR (petruui OR petrioi)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruuov OR petruiov) OR petruv) OR ((petruuo OR (petruui OR petrioi)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruuov OR petruiov) OR petruv) OR ((petruuo OR (petruui OR petrioi)) OR petr)) o.s.*.