Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), peteriov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petruov » petrov (Expand Search), peteruov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petroi » petro (Expand Search), petrov (Expand Search), petrow (Expand Search), peteroi (Expand Search), petruoi (Expand Search), petrooi (Expand Search)
peteri » peterdi (Expand Search), peter (Expand Search), peters (Expand Search)
petriuuv » peteriuuv (Expand Search), petruiuuv (Expand Search), petroiuuv (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 (petriuuv OR (((petriov OR petruov) OR (petroi OR peteri)) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petriuuv OR (((petriov OR petruov) OR (petroi OR peteri)) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petriuuv OR (((petriov OR petruov) OR (petroi OR peteri)) OR (petr OR petri))) o.s.*.