Perhaps you should try some spelling variations:
petruov » petrov (Expand Search), peteruov (Expand Search), petriuov (Expand Search), petrouov (Expand Search), pentruov (Expand Search), petriov (Expand Search)
petriov » petrov (Expand Search), peteriov (Expand Search), petriiov (Expand Search), petroiov (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search), pentru (Expand Search), petri (Expand Search)
petriuv » peteriuv (Expand Search), petriiuv (Expand Search), petroiuv (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 petriov) OR petriov) OR ((((petr OR petriov) OR petru) OR petriuv) OR per)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruov OR petriov) OR petriov) OR ((((petr OR petriov) OR petru) OR petriuv) OR per)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruov OR petriov) OR petriov) OR ((((petr OR petriov) OR petru) OR petriuv) OR per)) o.s.*.