Perhaps you should try some spelling variations:
petr » petri (Expand Search), petro (Expand Search), per (Expand Search)
petroi » petrioi (Expand Search), petrooi (Expand Search), peroi (Expand Search), petri (Expand Search), petro (Expand Search), petrov (Expand Search)
petru » petriu (Expand Search), petrou (Expand Search), peru (Expand Search), pentru (Expand Search), petri (Expand Search)
petruov » petriuov (Expand Search), petrouov (Expand Search), peruov (Expand Search), pentruov (Expand Search), petriov (Expand Search), petrov (Expand Search)
petriov » petriiov (Expand Search), petroiov (Expand Search), periov (Expand Search), petrov (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 (periv OR (((((petr OR peter) OR petroi) OR petru) OR (petruov OR petriov)) OR periv)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (periv OR (((((petr OR peter) OR petroi) OR petru) OR (petruov OR petriov)) OR periv)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (periv OR (((((petr OR peter) OR petroi) OR petru) OR (petruov OR petriov)) OR periv)) o.s.*.