Perhaps you should try some spelling variations:
perov » petrov (Expand Search)
peri » petri (Expand Search), per (Expand Search)
petruv » peteruv (Expand Search), petriuv (Expand Search), petrouv (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petruui » peteruui (Expand Search), petriuui (Expand Search), petrouui (Expand Search)
petruio » peteruio (Expand Search), petriuio (Expand Search), petrouio (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petro (Expand Search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: fop (((perov OR petruv) OR peruiiov) OR (((petru OR (peri OR petruui)) OR petruio) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((perov OR petruv) OR peruiiov) OR (((petru OR (peri OR petruui)) OR petruio) OR petr)) o.s.*".