Perhaps you should try some spelling variations:
petriiov » petrov (Expand Search), peteriiov (Expand Search), petriiiov (Expand Search), petruiiov (Expand Search)
peteruiv » peterdi (Expand Search)
petruov » peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petruiov (Expand Search)
petruiiv » peteruiiv (Expand Search), petriuiiv (Expand Search), petruuiiv (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 petriiov)) OR (peteriv OR peteruiv)) OR petruiiv) OR petr) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petruov OR (petriov OR petriiov)) OR (peteriv OR peteruiv)) OR petruiiv) OR petr) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petruov OR (petriov OR petriiov)) OR (peteriv OR peteruiv)) OR petruiiv) OR petr) o.s.*.