Perhaps you should try some spelling variations:
perov » petrov (Expand Search)
petriuiov » peteriuiov (Expand Search), petruiuiov (Expand Search), petroiuiov (Expand Search)
petruiiov » peteruiiov (Expand Search), petruuiiov (Expand Search), petrouiiov (Expand Search)
petruuuo » peteruuuo (Expand Search), petruuuuo (Expand Search), petrouuuo (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petroi » peteroi (Expand Search), petruoi (Expand Search), petrooi (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (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 ((perov OR (petriuiov OR petruiiov)) OR ((petruuuo OR (petri OR petroi)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((perov OR (petriuiov OR petruiiov)) OR ((petruuuo OR (petri OR petroi)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((perov OR (petriuiov OR petruiiov)) OR ((petruuuo OR (petri OR petroi)) OR petr)) o.s.*.