Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petriiuv » peteriiuv (Expand Search), petruiiuv (Expand Search), petroiiuv (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petriu » peteriu (Expand Search), petruiu (Expand Search), petroiu (Expand Search)
petriiu » peteriiu (Expand Search), petruiiu (Expand Search), petroiiu (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 (((petriov OR petriiuv) OR peterv) OR (((petri OR per) OR (petriu OR petriiu)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR petriiuv) OR peterv) OR (((petri OR per) OR (petriu OR petriiu)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR petriiuv) OR peterv) OR (((petri OR per) OR (petriu OR petriiu)) OR petr)) o.s.*.