Lucene：文件存在，而无法通过使用QueryParser获取文件

基本上，我为85k html文件建立了索引（google结果页面和关键字是不同的大学名称），并且我将每个页面的标题用作我的lucene索引中名为“ title”的字段。当我搜索“ duquesne AND university”之类的关键词时，没有结果出来，但是，当我仅将关键词更改为“ duquesne”时，我可以得到标题为：“ title：Duquesne Univeristy-Google搜索”的结果，为什么发生这种情况吗？从第二次尝试中，我可以告诉您该标题为Duquesne Univeristy的文件已被索引，但我无法从第一次尝试中获取它。多谢！〜

这是我用于建立索引的代码，我使用Jsoup从网页获取标题：

//indexDir is the directory that hosts Lucene's index files 
     File   indexDir = new File("F:\\luceneIndex"); 

     Directory myindex=SimpleFSDirectory.open(indexDir);
     //dataDir is the directory that hosts the text files that to be indexed 
     File   dataDir  = new File("I:\\luceneTextFiles"); 
     Analyzer luceneAnalyzer = new StandardAnalyzer(Version.LUCENE_CURRENT); 
     File[] dataFiles  = dataDir.listFiles(); 
     IndexWriterConfig indexConfig=new IndexWriterConfig(Version.LUCENE_CURRENT,luceneAnalyzer);
     IndexWriter indexWriter = new IndexWriter(myindex, indexConfig); 
     long startTime = new Date().getTime(); 
     System.out.println("Total file number is  "+dataFiles.length+"");
     for(int i = 0; i < dataFiles.length; i++){ 
          if(dataFiles[i].isFile() && dataFiles[i].getName().endsWith(".txt")){
               org.jsoup.nodes.Document t=Jsoup.parse(dataFiles[i], "UTF-8");                  
               Document document = new Document(); 
               Reader txtReader = new FileReader(dataFiles[i]); 
               document.add(new Field("title",t.title(),Field.Store.YES,Field.Index.ANALYZED));
               document.add(new Field("path",dataFiles[i].getCanonicalPath(),Field.Store.YES,Field.Index.NOT_ANALYZED)); 
               document.add(new Field("count",i+"",Field.Store.YES,Field.Index.NOT_ANALYZED));
               document.add(new Field("contents",txtReader)); 
               indexWriter.addDocument(document); 

          } 
     } 

     //indexWriter.getCommitData();
     indexWriter.close(); 
     long endTime = new Date().getTime(); 

String queryKey="duquesne";
        String subqueryKey="university";
        String queryField="contents";
        String subqueryField="title";
        /*
         * 0------>normal search
         * 1------>range search
         * 2------>prefix search
         * 3------>combine search
         * 4------>phrase query
         * 5------>wild card query
         * 6------>fuzzy query
         */
        int querychoice=0;

        //initialize the directory
        File indexDir=new File("F:\\luceneIndex");
        Directory directory=SimpleFSDirectory.open(indexDir);
        IndexReader reader=IndexReader.open(directory);
        //initialize the searcher
        IndexSearcher searcher=new IndexSearcher(reader);
        Analyzer analyzer=new StandardAnalyzer(Version.LUCENE_CURRENT);
        Query query;
        switch(querychoice){

        case 0:
            QueryParser parser=new QueryParser(Version.LUCENE_CURRENT,subqueryField,analyzer);
            query=parser.parse(queryKey);
            break;