Perhaps you should try some spelling variations:
peruv » perv (Expand Search)
peru » per (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petroiov (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petriuo » peteriuo (Expand Search), petriiuo (Expand Search), petroiuo (Expand Search)
petriiiuo » peteriiiuo (Expand Search), petriiiiuo (Expand Search), petroiiiuo (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 ((petriov OR peruv) OR (((pero OR (petru OR peru)) OR (petriuo OR petriiiuo)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR peruv) OR (((pero OR (petru OR peru)) OR (petriuo OR petriiiuo)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriov OR peruv) OR (((pero OR (petru OR peru)) OR (petriuo OR petriiiuo)) OR petr)) o.s.*.