Nokogiri XML::NodeSet#search behavior

[Trans]

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
<root><x><m id="a" class="q">dummy</m><n id="b" class="q">dummy</
n></x></root>
EOS

nodeset = xml.search('.q')

p nodeset
<m id="a" class="q">dummy</m><n id="b" class="q">dummy</n>

p nodeset.search('#a')
=> nil

T.