title: XPath from Chrome results in an empty list in scrapy
body: <p>I'm inspecting a page by Chrome Dev Tools and have xpath of an element on the page. I disable javascript deliberately so DOM doesn't get changed. However, xpath I Chrome gives for the element results in <code>[]</code> in scrapy, although the element, of course, exists. What might be the problem?</p>
  
  <p>In particular, xpath <code>//*[@id="prddeatailed_container"]/table[1]/tbody/tr[1]/td/div/table/tbody/tr[2]/td[1]/span</code> for this <a href="http://cheaptool.ru/product/sadovyj-pylesos-billy-goat-lb351/" rel="nofollow">http://cheaptool.ru/product/sadovyj-pylesos-billy-goat-lb351/</a> - the price 29 990.</p>
  
  <pre><code>$ scrapy shell 'http://cheaptool.ru/product/sadovyj-pylesos-billy-goat-lb351'
  
  In [2]: xp1 = '//*[@id="prddeatailed_container"]/table[1]/tbody/tr[1]/td/div/table/tbody/tr[2]/td[1]/span'
  
  In [3]: aaa = response.xpath(xp1)
  
  In [4]: aaa
  Out[4]: []
  </code></pre>
  
  <p><strong>UPDATE:</strong>
  It turned out in the result html there was no tbody. Why did Chrome showed it in xpath? How to make it the real html in xpath?</p>