Perhaps you should try some spelling variations:
petrov » peterov (Expand Search), petriov (Expand Search), petruov (Expand Search)
petriou » peteriou (Expand Search), petriiou (Expand Search), petruiou (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petruuo (Expand Search)
petriuo » peteriuo (Expand Search), petriiuo (Expand Search), petruiuo (Expand Search)
petrouiuo » peterouiuo (Expand Search), petriouiuo (Expand Search), petruouiuo (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (Expand Search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: fop (petrov OR ((petriou OR ((petruo OR petriuo) OR (petrouiuo OR peterouiuo))) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petrov OR ((petriou OR ((petruo OR petriuo) OR (petrouiuo OR peterouiuo))) OR petr)) o.s.*".