Perhaps you should try some spelling variations:
petriiov » petrov (Expand Search), peteriiov (Expand Search), petriiiov (Expand Search), petroiiov (Expand Search)
peteruov » petrov (Expand Search)
peri » petri (Expand Search), per (Expand Search)
petrv » peterv (Expand Search), petriv (Expand Search), petrov (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petroui (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (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 ((((petriiov OR peteruv) OR peteruov) OR petrv) OR ((petru OR (peri OR petrui)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petriiov OR peteruv) OR peteruov) OR petrv) OR ((petru OR (peri OR petrui)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petriiov OR peteruv) OR peteruov) OR petrv) OR ((petru OR (peri OR petrui)) OR petr)) o.s.*.