Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petrv » peterv (Expand Search), petriv (Expand Search), petruv (Expand Search)
petruv » peteruv (Expand Search), petriuv (Expand Search), petruuv (Expand Search)
petruiv » peteruiv (Expand Search), petriuiv (Expand Search), petruuiv (Expand Search)
petrov » peterov (Expand Search), petriov (Expand Search), petruov (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 (((petrv OR petruv) OR petruiv) OR peterv)) OR ((petrov OR peteru) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR (((petrv OR petruv) OR petruiv) OR peterv)) OR ((petrov OR peteru) OR petr)) o.s.*".