Perhaps you should try some spelling variations:
petriiov » petrov (Expand Search), peteriiov (Expand Search), petruiiov (Expand Search), petroiiov (Expand Search)
petruiov » petrov (Expand Search), peteruiov (Expand Search), petruuiov (Expand Search), petrouiov (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petruo » peteruo (Expand Search), petruuo (Expand Search), petrouo (Expand Search)
petruuo » peteruuo (Expand Search), petruuuo (Expand Search), petrouuo (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: fop ((petriiov OR petruiov) OR ((petri OR (petruo OR petruuo)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriiov OR petruiov) OR ((petri OR (petruo OR petruuo)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriiov OR petruiov) OR ((petri OR (petruo OR petruuo)) OR petr)) o.s.*.