Perhaps you should try some spelling variations:
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petriiiv » peteriiiv (Expand Search), petriiiiv (Expand Search), petruiiiv (Expand Search)
petruuiv » peteruuiv (Expand Search), petriuuiv (Expand Search), petruuuiv (Expand Search)
petruuio » peteruuio (Expand Search), petriuuio (Expand Search), petruuuio (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 petriov) OR (petriiiv OR petruuiv)) OR peterov) OR (petruuio OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petruov OR petriov) OR (petriiiv OR petruuiv)) OR peterov) OR (petruuio OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petruov OR petriov) OR (petriiiv OR petruuiv)) OR peterov) OR (petruuio OR petr)) o.s.*.