Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
peterov » petrov (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search), petri (Expand Search), petro (Expand Search), petrov (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petruui (Expand Search), petri (Expand Search), petru (Expand Search)
peteri » peterdi (Expand Search), peter (Expand Search), petri (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 peterov) OR (petr OR (petroi OR peteri))) OR (peteri OR petrui)) _. s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR peterov) OR (petr OR (petroi OR peteri))) OR (peteri OR petrui)) _. s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR peterov) OR (petr OR (petroi OR peteri))) OR (peteri OR petrui)) _. s.*.