Perhaps you should try some spelling variations:
peterov » petrov (Expand Search)
petru » pentru (Expand Search), peteru (Expand Search), petrou (Expand Search), peru (Expand Search)
petruuuo » pentruuuo (Expand Search), peteruuuo (Expand Search), petrouuuo (Expand Search), peruuuo (Expand Search)
petriuuv » peteriuuv (Expand Search), petroiuuv (Expand Search), periuuv (Expand Search)
petrouuo » peterouuo (Expand Search), petroouuo (Expand Search), perouuo (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 ((petriuuv OR peterov) OR ((petru OR (petruuuo OR petrouuo)) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriuuv OR peterov) OR ((petru OR (petruuuo OR petrouuo)) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriuuv OR peterov) OR ((petru OR (petruuuo OR petrouuo)) OR (petr OR petri))) o.s.*.