Perhaps you should try some spelling variations:
petruv » petru (Expand Search), petrov (Expand Search), peteruv (Expand Search), petruuv (Expand Search), petrouv (Expand Search)
peterov » petrov (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petruuo » peteruuo (Expand Search), petruuuo (Expand Search), petrouuo (Expand Search)
peteri » peterdi (Expand Search), peter (Expand Search), peters (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 ((petruv OR peterov) OR ((((petr OR petri) OR peteri) OR (peteruo OR petruuo)) OR per)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruv OR peterov) OR ((((petr OR petri) OR peteri) OR (peteruo OR petruuo)) OR per)) o.s.*".