Perhaps you should try some spelling variations:
petrovw » petrov (Expand Search), petrow (Expand Search), petrovvw (Expand Search), petruvw (Expand Search), peterovw (Expand Search), petruovw (Expand Search)
petro » petrov (Expand Search), petru (Expand Search), petero (Expand Search), petruo (Expand Search)
petroi » petrovi (Expand Search), petrui (Expand Search), peteroi (Expand Search), petruoi (Expand Search), petrov (Expand Search), petrow (Expand Search)
petr » peter (Expand Search), petru (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search)
peteroi » peterdi (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 (((petrovw OR petro) o) OR ((((petr OR petri) OR (petroi OR peteroi)) OR per) _)). s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petrovw OR petro) o) OR ((((petr OR petri) OR (petroi OR peteroi)) OR per) _)). s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petrovw OR petro) o) OR ((((petr OR petri) OR (petroi OR peteroi)) OR per) _)). s.*.