Perhaps you should try some spelling variations:
petriuov » petrov (Expand Search), peteriuov (Expand Search), petriiuov (Expand Search), petroiuov (Expand Search)
perov » petrov (Expand Search)
petruiov » petrov (Expand Search), peteruiov (Expand Search), petriuiov (Expand Search), petrouiov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petroiov (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (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 (((petriuov OR perov) OR (petriov OR petruiov)) OR (((petru OR perov) OR peteri) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriuov OR perov) OR (petriov OR petruiov)) OR (((petru OR perov) OR peteri) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriuov OR perov) OR (petriov OR petruiov)) OR (((petru OR perov) OR peteri) OR petr)) o.s.*.