Perhaps you should try some spelling variations:
petriiv » peteriiv (Expand Search), petriiiv (Expand Search), petruiiv (Expand Search)
petruiiv » peteruiiv (Expand Search), petriuiiv (Expand Search), petruuiiv (Expand Search)
petruuv » peteruuv (Expand Search), petriuuv (Expand Search), petruuuv (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petruui (Expand Search)
petriuo » peteriuo (Expand Search), petriiuo (Expand Search), petruiuo (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 (((petriiv OR petruiiv) OR petruuv) OR (((petruov OR petrui) OR petriuo) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriiv OR petruiiv) OR petruuv) OR (((petruov OR petrui) OR petriuo) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriiv OR petruiiv) OR petruuv) OR (((petruov OR petrui) OR petriuo) OR petr)) o.s.*.