Nokogiri XML::NodeSet#search behavior

Can a Nokogiri NodeSet not be searched? There is a #search method but
it doesn’t seem to work as I would expect it too.

require ‘nokogiri’

xml = Nokogiri::XML <<-EOS
dummydummy</
n>
EOS

nodeset = xml.search(’.q’)

p nodeset
dummydummy

p nodeset.search(’#a’)
=> nil

T.