Perhaps you should try some spelling variations:
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)
petroou » petruoou (Expand Search), petrooou (Expand Search), peroou (Expand Search)
petrov » petruov (Expand Search), petroov (Expand Search), perov (Expand Search), petro (Expand Search)
petrooov » petruooov (Expand Search), petroooov (Expand Search), perooov (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search), peri (Expand Search)
petruoi » petruuoi (Expand Search), petrouoi (Expand Search), peruoi (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 ((((petr OR (petroou OR petrov)) OR petrooov) OR (petri OR petruoi)) OR peter) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petr OR (petroou OR petrov)) OR petrooov) OR (petri OR petruoi)) OR peter) o.s.*".