Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), petriiov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petrv » petrov (Expand Search), petri (Expand Search), petru (Expand Search), petriv (Expand Search), petruv (Expand Search)
petruv » petru (Expand Search), petrov (Expand Search), petriuv (Expand Search), petruuv (Expand Search), petrouv (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (Expand Search)
petrou » petriou (Expand Search), petruou (Expand Search), petroou (Expand Search), petru (Expand Search), petro (Expand Search), petrov (Expand Search)
petrioou » petriioou (Expand Search), petruioou (Expand Search), petroioou (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 (((petrv OR petruv) OR petr) OR petriov)) OR ((petrou OR petrioou) OR peter)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR (((petrv OR petruv) OR petr) OR petriov)) OR ((petrou OR petrioou) OR peter)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriov OR (((petrv OR petruv) OR petr) OR petriov)) OR ((petrou OR petrioou) OR peter)) o.s.*.