Perhaps you should try some spelling variations:
petriow » petrow (Expand Search), petriiow (Expand Search), petruiow (Expand Search), petroiow (Expand Search)
petrovw » petrov (Expand Search), petrow (Expand Search), petriovw (Expand Search), petruovw (Expand Search), petroovw (Expand Search)
petruvw » petriuvw (Expand Search), petruuvw (Expand Search), petrouvw (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (Expand Search)
petriv » petriiv (Expand Search), petruiv (Expand Search), petroiv (Expand Search), petri (Expand Search), petris (Expand Search), petrov (Expand Search)
peters » petersen (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 ((((petriow OR petrovw) OR petruvw) o) OR (((petr OR (peters OR peter)) OR petriv) _)). s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petriow OR petrovw) OR petruvw) o) OR (((petr OR (peters OR peter)) OR petriv) _)). s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petriow OR petrovw) OR petruvw) o) OR (((petr OR (peters OR peter)) OR petriv) _)). s.*.