Perhaps you should try some spelling variations:
peri » per (Expand Search)
petrv » peterv (Expand Search), petruv (Expand Search), petrov (Expand Search)
petruv » peteruv (Expand Search), petruuv (Expand Search), petrouv (Expand Search)
petrov » peterov (Expand Search), petruov (Expand Search), petroov (Expand Search)
petruov » peteruov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petruo » peteruo (Expand Search), petruuo (Expand Search), petrouo (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 ((petrv OR petruv) OR ((petrov OR petruov) OR ((petruo OR (petri OR peri)) OR petr))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petrv OR petruv) OR ((petrov OR petruov) OR ((petruo OR (petri OR peri)) OR petr))) o.s.*".