Perhaps you should try some spelling variations:
petruov » petrov (Expand Search), peteruov (Expand Search), petriuov (Expand Search), petruuov (Expand Search)
petra » petri (Expand Search), petru (Expand Search), petro (Expand Search), petera (Expand Search), petria (Expand Search), petrua (Expand Search)
petrio » petri (Expand Search), petro (Expand Search), peterio (Expand Search), petriio (Expand Search), petruio (Expand Search)
petris » petri (Expand Search), peteris (Expand Search), petriis (Expand Search), petruis (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 (((petruov OR peteruouov) OR petra) OR ((petrio OR petris) OR (petr OR peterdi))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petruov OR peteruouov) OR petra) OR ((petrio OR petris) OR (petr OR peterdi))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petruov OR peteruouov) OR petra) OR ((petrio OR petris) OR (petr OR peterdi))) o.s.*.