Perhaps you should try some spelling variations:
petrow » petro (Expand Search), petrov (Expand Search), petroow (Expand Search), perow (Expand Search)
petrowna » petrona (Expand Search), petrovna (Expand Search), petroowna (Expand Search), perowna (Expand Search)
petruuv » petrouuv (Expand Search), peruuv (Expand Search), pentruuv (Expand Search)
petr » petro (Expand Search), per (Expand Search)
petri » petroi (Expand Search), peri (Expand Search)
petru » petrou (Expand Search), peru (Expand Search), pentru (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 ((petruuv OR peteruv) OR ((petrow OR petrowna) OR (((petr OR petri) OR petru) OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruuv OR peteruv) OR ((petrow OR petrowna) OR (((petr OR petri) OR petru) OR peter))) o.s.*".