Perhaps you should try some spelling variations:
petruoov » petrov (Expand Search), peteruoov (Expand Search), petruuoov (Expand Search), petrouoov (Expand Search)
peteroui » peterdi (Expand Search)
petriv » peteriv (Expand Search), petruiv (Expand Search), petroiv (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petruooui » peteruooui (Expand Search), petruuooui (Expand Search), petrouooui (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (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 (((peterov OR petruoov) OR petriv) OR ((petri OR (peteroui OR petruooui)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((peterov OR petruoov) OR petriv) OR ((petri OR (peteroui OR petruooui)) OR petr)) o.s.*".