title: Is solr4 capable of cross-core join with multi-conditions
body: <p>solr4 introduced join feature, so we can use the url below:</p>
  
  <pre><code> {!join from=fromField to=toField fromIndex=fromCoreName}news_headline:apple
  </code></pre>
  
  <p>but i have such a scenario, not only news_headline is needed, but also the news_type, how can i add news_type in this url?                       </p>