title: Usage of lucene's MultiFieldQueryParser
body: <p>In lucene 5.3, while trying to use <code>MultiFieldQueryParser</code> to parse a raw string into a <code>Query</code> instance, and do search, then it seems the search result is not correct.</p>
  
  <p><strong>Data</strong>:</p>
  
  <p>There is a document with <code>city</code> field as <code>Venice</code>.</p>
  
  <p><strong>Code</strong>:</p>
  
  <pre><code>public void testQueryParser() throws IOException, ParseException {
      QueryParser parser = new MultiFieldQueryParser(new String[] { "city" }, new SimpleAnalyzer());
      Query query = parser.parse("Venice");
  
      IndexSearcher searcher = new IndexSearcher(getReader());
      TopDocs docs = searcher.search(query, 10);
      assertEquals(1, docs.totalHits); // FIXME ... seems failed,
  }
  </code></pre>
  
  <p>The above junit expect the totalHits to be <code>1</code>, but get <code>0</code>.</p>
  
  <p>Any help? thanks.</p>