Perhaps you should try some spelling variations:
peteriov » petrov (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petriuuov » peteriuuov (Expand Search), petriiuuov (Expand Search), petruiuuov (Expand Search)
petruou » peteruou (Expand Search), petriuou (Expand Search), petruuou (Expand Search)
petruuio » peteruuio (Expand Search), petriuuio (Expand Search), petruuuio (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 (((petruov OR petriuuov) OR peteriov) OR ((petruou OR peteruou) OR (petruuio OR petr))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruov OR petriuuov) OR peteriov) OR ((petruou OR peteruou) OR (petruuio OR petr))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruov OR petriuuov) OR peteriov) OR ((petruou OR peteruou) OR (petruuio OR petr))) o.s.*.