Perhaps you should try some spelling variations:
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)
petrov » petruov (Expand Search), petroov (Expand Search), perov (Expand Search), petro (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search), peri (Expand Search)
petrui » petruui (Expand Search), petroui (Expand Search), perui (Expand Search), petru (Expand Search)
petroui » petruoui (Expand Search), petrooui (Expand Search), peroui (Expand Search)
petruuo » petruuuo (Expand Search), petrouuo (Expand Search), peruuo (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 (peruv OR ((((petr OR petrov) OR (petri OR (petrui OR petroui))) OR petruuo) OR peter)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (peruv OR ((((petr OR petrov) OR (petri OR (petrui OR petroui))) OR petruuo) OR peter)) o.s.*".