Perhaps you should try some spelling variations:
petruoov » petrov (Expand Search), peteruoov (Expand Search), petruuoov (Expand Search), petrouoov (Expand Search)
petroiv » peteroiv (Expand Search), petruoiv (Expand Search), petrooiv (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petroi » peteroi (Expand Search), petruoi (Expand Search), petrooi (Expand Search)
petrooui » peterooui (Expand Search), petruooui (Expand Search), petroooui (Expand Search)
petr » peter (Expand Search), petru (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 ((petruoov OR (petroiv OR peterooiv)) OR (((petri OR petroi) OR petrooui) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruoov OR (petroiv OR peterooiv)) OR (((petri OR petroi) OR petrooui) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petruoov OR (petroiv OR peterooiv)) OR (((petri OR petroi) OR petrooui) OR petr)) o.s.*.