Perhaps you should try some spelling variations:
petriiv » peteriiv (Expand Search), petriiiv (Expand Search), petruiiv (Expand Search)
petruiv » peteruiv (Expand Search), petriuiv (Expand Search), petruuiv (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petruuo (Expand Search)
petruuo » peteruuo (Expand Search), petriuuo (Expand Search), petruuuo (Expand Search)
petriioi » peteriioi (Expand Search), petriiioi (Expand Search), petruiioi (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 petruiv) OR (((petruo OR petruuo) OR (petriioi OR petriioi)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriiv OR petruiv) OR (((petruo OR petruuo) OR (petriioi OR petriioi)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriiv OR petruiv) OR (((petruo OR petruuo) OR (petriioi OR petriioi)) OR petr)) o.s.*.