lucene.net 查询的问题

Question

最近在学习lucene.net，跟着网上的例子学着做了一个例子，但是不知道为什么搜索索引的时候hits.length总是0，请帮忙看一下，谢谢

        #region 索引条件
        public ActionResult ResumeIndexSearch()
        {
            List<string> list = new List<string>() {"北京","三年","java"};
            for (int i = 0; i < list.Count; i++)
            {
                IndexSearch(list[i]);
            }
            return View("ResumeQuickSearch");
        }
        #endregion

 

        #region 搜索索引
        public void IndexSearch(String queryString)
        {
            EntityList list = new EntityList();
            Hits hits = null;
            try
            {
                IndexSearcher searcher = new IndexSearcher("d:/index");
                queryString = GetKeyWordsSplitBySpace(queryString, new KTDictSegTokenizer());

                QueryParser contentParser = new QueryParser("content", new KTDictSegAnalyzer());
                Query contentQuery = contentParser.Parse(queryString);

                QueryParser cityParser = new QueryParser("city", new KTDictSegAnalyzer());
                Query cityQuery = contentParser.Parse(queryString);

                QueryParser skillParser = new QueryParser("skill", new KTDictSegAnalyzer());
                Query skillQuery = contentParser.Parse(queryString);

                BooleanQuery bquery = new BooleanQuery();
                bquery.Add(contentQuery, BooleanClause.Occur.MUST);
                bquery.Add(cityQuery, BooleanClause.Occur.MUST);
                bquery.Add(skillQuery, BooleanClause.Occur.MUST);

                hits = searcher.Search(bquery);

                System.Web.HttpContext.Current.Response.Write("------------hits:" + hits.Length() + "\r\n\\");

                ArrayList entities = new ArrayList();
                for (int i = 0; i < hits.Length(); i++)
                {
                    Document doc = hits.Doc(i);
                    LuceneEntity entity = new LuceneEntity();
                    entity.Id = doc.Get("id");
                    entity.Title = doc.Get("name");
                    entity.Type = doc.Get("type");
                    entity.URL = doc.Get("url");
                    entity.Content = doc.Get("content");
                    entity.CreateDate = doc.Get("time");
                    entities.Add(entity);
                    System.Web.HttpContext.Current.Response.Write("------------content id:" + doc.Get("id") + "\r\n\\");
                }
                list.Count = hits.Length();
                list.List = entities;
                searcher.Close();
            }
            catch(Exception e)
            {
                System.Web.HttpContext.Current.Response.Write("----------error:" + e.Message + "---" + e.ToString());
            }
        }
        #endregion