def normalize
      ActiveSupport::Multibyte::Chars.new(self).
        mb_chars.normalize(:kd).gsub(/[^\x00-\x7F]/,'').downcase.to_s.
        gsub(/[^a-z]/,' ').
        gsub(/\s+/,'*').
        gsub(/^/,'**').
        gsub(/$/,'*')
    end
def normalize
      ActiveSupport::Multibyte::Chars.new(self).
        mb_chars.normalize(:kd).gsub(/[^\x00-\x7F]/,'').downcase.to_s.
        gsub(/[^a-z]/,' ').
        gsub(/\s+/,'*').
        gsub(/^/,'**').
        gsub(/$/,'*')
    end
Remove accents, downcase, replace spaces and word start with '*',
 return list of normalized words