Perhaps you should try some spelling variations:
petriv » petris (Expand Search), petruiv (Expand Search), petroiv (Expand Search), periv (Expand Search)
petrov » petro (Expand Search), petruov (Expand Search), petroov (Expand Search), perov (Expand Search)
petroov » petruoov (Expand Search), petrooov (Expand Search), peroov (Expand Search)
petrooov » petruooov (Expand Search), petroooov (Expand Search), perooov (Expand Search)
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search), peri (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 ((petriv OR (petrov OR (petroov OR petrooov))) OR (petr OR (petri OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriv OR (petrov OR (petroov OR petrooov))) OR (petr OR (petri OR peter))) o.s.*".