Perhaps you should try some spelling variations:
petriuov » petrov (Expand Search), peteriuov (Expand Search), petriiuov (Expand Search), petruiuov (Expand Search)
petruiuov » peteruiuov (Expand Search), petriuiuov (Expand Search), petruuiuov (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petruui (Expand Search)
petriui » peteriui (Expand Search), petriiui (Expand Search), petruiui (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 (((petriuov OR peteriuov) OR petruiuov) OR ((petroi OR (petrui OR petriui)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petriuov OR peteriuov) OR petruiuov) OR ((petroi OR (petrui OR petriui)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petriuov OR peteriuov) OR petruiuov) OR ((petroi OR (petrui OR petriui)) OR petr)) o.s.*.