Perhaps you should try some spelling variations:
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petruuv » peteruuv (Expand Search), petriuuv (Expand Search), petruuuv (Expand Search)
petruiuv » peteruiuv (Expand Search), petriuiuv (Expand Search), petruuiuv (Expand Search)
petriuuou » peteriuuou (Expand Search), petriiuuou (Expand Search), petruiuuou (Expand Search)
petruuuou » peteruuuou (Expand Search), petriuuuou (Expand Search), petruuuuou (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 ((petriov OR ((petruuv OR petruiuv) OR peteruv)) OR ((petriuuou OR petruuuou) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR ((petruuv OR petruiuv) OR peteruv)) OR ((petriuuou OR petruuuou) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriov OR ((petruuv OR petruiuv) OR peteruv)) OR ((petriuuou OR petruuuou) OR petr)) o.s.*.