Perhaps you should try some spelling variations:
petrois » petris (Expand Search), petruois (Expand Search), petroois (Expand Search), perois (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search), peri (Expand Search)
petriov » petruiov (Expand Search), petroiov (Expand Search), periov (Expand Search)
petroiiu » petruoiiu (Expand Search), petrooiiu (Expand Search), peroiiu (Expand Search)
petr » petru (Expand Search), petro (Expand Search), per (Expand Search)
petrov » petruov (Expand Search), petroov (Expand Search), perov (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 (petrois OR (((petri OR petriov) OR petroiiu) OR ((petr OR petrov) OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petrois OR (((petri OR petriov) OR petroiiu) OR ((petr OR petrov) OR peter))) o.s.*".