Perhaps you should try some spelling variations:
peru » petru (Expand Search), per (Expand Search)
peri » petri (Expand Search), per (Expand Search)
petriuv » peteriuv (Expand Search), petriiuv (Expand Search), petruiuv (Expand Search)
petruv » peteruv (Expand Search), petriuv (Expand Search), petruuv (Expand Search)
petruo » peteruo (Expand Search), petriuo (Expand Search), petruuo (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (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 ((petriuv OR (petruv OR peteruv)) OR ((((petruo OR peru) OR petriov) OR peri) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriuv OR (petruv OR peteruv)) OR ((((petruo OR peru) OR petriov) OR peri) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriuv OR (petruv OR peteruv)) OR ((((petruo OR peru) OR petriov) OR peri) OR petr)) o.s.*.