Perhaps you should try some spelling variations:
petroou » peteroou (Expand Search), petruoou (Expand Search), petrooou (Expand Search)
petrouo » peterouo (Expand Search), petruouo (Expand Search), petroouo (Expand Search)
petriuo » peteriuo (Expand Search), petruiuo (Expand Search), petroiuo (Expand Search)
petrouuo » peterouuo (Expand Search), petruouuo (Expand Search), petroouuo (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 (periov OR ((petroou OR ((petrouo OR petriuo) OR petrouuo)) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (periov OR ((petroou OR ((petrouo OR petriuo) OR petrouuo)) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (periov OR ((petroou OR ((petrouo OR petriuo) OR petrouuo)) OR (petr OR petri))) o.s.*.