Perhaps you should try some spelling variations:
petriiov » petrov (Expand Search), peteriiov (Expand Search), petriiiov (Expand Search), petruiiov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petroov » peteroov (Expand Search), petrioov (Expand Search), petruoov (Expand Search)
petrou » peterou (Expand Search), petriou (Expand Search), petruou (Expand Search)
petruiuou » peteruiuou (Expand Search), petriuiuou (Expand Search), petruuiuou (Expand Search)
petruiiiou » peteruiiiou (Expand Search), petriuiiiou (Expand Search), petruuiiiou (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 petriiov) OR petroov) OR (((petrou OR petruiuou) OR petruiiiou) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriov OR petriiov) OR petroov) OR (((petrou OR petruiuou) OR petruiiiou) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriov OR petriiov) OR petroov) OR (((petrou OR petruiuou) OR petruiiiou) OR petr)) o.s.*.