Perhaps you should try some spelling variations:
petriiv » peteriiv (Expand Search), petriiiv (Expand Search), petroiiv (Expand Search)
petroiiiuv » peteroiiiuv (Expand Search), petrioiiiuv (Expand Search), petrooiiiuv (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petriu » peteriu (Expand Search), petriiu (Expand Search), petroiu (Expand Search)
petrio » peterio (Expand Search), petriio (Expand Search), petroio (Expand Search)
petr » peter (Expand Search), petri (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 ((petriiv OR petroiiiuv) OR ((((pero OR (petru OR petriu)) OR petrio) OR petero) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriiv OR petroiiiuv) OR ((((pero OR (petru OR petriu)) OR petrio) OR petero) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriiv OR petroiiiuv) OR ((((pero OR (petru OR petriu)) OR petrio) OR petero) OR petr)) o.s.*.