Perhaps you should try some spelling variations:
petriv » petris (Expand Search), petrov (Expand Search), peteriv (Expand Search), petroiv (Expand Search), periv (Expand Search)
petriov » petrov (Expand Search), peteriov (Expand Search), petroiov (Expand Search), periov (Expand Search)
petero » peter (Expand Search), peters (Expand Search), petro (Expand Search)
peterov » peterv (Expand Search), petersv (Expand Search), petrov (Expand Search)
petru » pentru (Expand Search), peteru (Expand Search), petrou (Expand Search), peru (Expand Search)
petr » peter (Expand Search), petro (Expand Search), per (Expand Search)
petri » peteri (Expand Search), petroi (Expand Search), peri (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 (((petriv OR peteriv) OR petriov) OR (((petero OR petru) OR peterov) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriv OR peteriv) OR petriov) OR (((petero OR petru) OR peterov) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriv OR peteriv) OR petriov) OR (((petero OR petru) OR peterov) OR (petr OR petri))) o.s.*.