Perhaps you should try some spelling variations:
petru » pentru (Expand Search), petrou (Expand Search), peru (Expand Search)
petrv » petrov (Expand Search), petro (Expand Search), petra (Expand Search), perv (Expand Search)
petroa » petro (Expand Search), petrov (Expand Search), petra (Expand Search), petrooa (Expand Search), peroa (Expand Search)
petriv » petris (Expand Search), petrov (Expand Search), petroiv (Expand Search), periv (Expand Search)
petri » petroi (Expand Search), peri (Expand Search)
petr » petro (Expand Search), per (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 ((petru OR ((petrv OR petroa) OR (petriv OR petri))) OR (perou OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petru OR ((petrv OR petroa) OR (petriv OR petri))) OR (perou OR (petr OR peter))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petru OR ((petrv OR petroa) OR (petriv OR petri))) OR (perou OR (petr OR peter))) o.s.*.