Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petriiiov » peteriiiov (Expand Search), petruiiiov (Expand Search), petroiiiov (Expand Search)
petrov » peterov (Expand Search), petruov (Expand Search), petroov (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petrui » peterui (Expand Search), petruui (Expand Search), petroui (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 ((petriov OR (peteriiov OR petriiiov)) OR ((petrov OR (petri OR petrui)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR (peteriiov OR petriiiov)) OR ((petrov OR (petri OR petrui)) OR petr)) o.s.*".