Perhaps you should try some spelling variations:
petroiov » petrov (Expand Search), peteroiov (Expand Search), petrioiov (Expand Search), petrooiov (Expand Search)
perov » petrov (Expand Search)
peri » petri (Expand Search), per (Expand Search)
petriiiov » peteriiiov (Expand Search), petriiiiov (Expand Search), petroiiiov (Expand Search)
petrio » peterio (Expand Search), petriio (Expand Search), petroio (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petr » peter (Expand Search), petri (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 (((petroiov OR perov) OR petriiiov) OR (((petrio OR petru) OR (peteri OR peri)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((petroiov OR perov) OR petriiiov) OR (((petrio OR petru) OR (peteri OR peri)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (((petroiov OR perov) OR petriiiov) OR (((petrio OR petru) OR (peteri OR peri)) OR petr)) o.s.*.