Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), peteriov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petriu » petru (Expand Search), petris (Expand Search), peteriu (Expand Search), petruiu (Expand Search), petroiu (Expand Search)
petrioio » peterioio (Expand Search), petruioio (Expand Search), petroioio (Expand Search)
petruiio » peteruiio (Expand Search), petruuiio (Expand Search), petrouiio (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 ((petriov OR peteriv) OR (((petrioio OR petruiio) OR petriu) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR peteriv) OR (((petrioio OR petruiio) OR petriu) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriov OR peteriv) OR (((petrioio OR petruiio) OR petriu) OR (petr OR petri))) o.s.*.