Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), petriv (Expand Search), petrisv (Expand Search), peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
peters » peter (Expand Search), petersen (Expand Search)
petrio » petri (Expand Search), petris (Expand Search), petro (Expand Search), peterio (Expand Search), petriio (Expand Search), petruio (Expand Search)
petrou » petru (Expand Search), petro (Expand Search), petrov (Expand Search), peterou (Expand Search), petriou (Expand Search), petruou (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (Expand Search)
peteri » 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 ((((peters OR petrio) OR peters) OR petrou) OR (petr OR (peteri OR peterdi)))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petriov OR ((((peters OR petrio) OR peters) OR petrou) OR (petr OR (peteri OR peterdi)))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petriov OR ((((peters OR petrio) OR peters) OR petrou) OR (petr OR (peteri OR peterdi)))) o.s.*.