Perhaps you should try some spelling variations:
petruuov » petrov (Expand Search), peteruuov (Expand Search), petriuuov (Expand Search), petruuuov (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petriui » peteriui (Expand Search), petriiui (Expand Search), petruiui (Expand Search)
petriio » peteriio (Expand Search), petriiio (Expand Search), petruiio (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 ((petruov OR petruuov) OR (((petriov OR petriui) OR (petriio OR peterio)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruov OR petruuov) OR (((petriov OR petriui) OR (petriio OR peterio)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petruov OR petruuov) OR (((petriov OR petriui) OR (petriio OR peterio)) OR petr)) o.s.*.