一个搜寻节点并删除添加的问题！

<html>
<head>
</head>
<body>
<table border=1>
<!-- 这里可能有很多的trtd    -->
<tr>
              <td>&nbsp;</td>
              <td>
                <textarea id="replyContent" name="content" ></textarea>
              </td>
</tr>
 <tr>
              <td>HAHA</td>
              <td>
                <div>
                 <script language="javascript">
                   document.write('Test');
                 </script>
                </div>
</td>
</tr> 
</table>
<div ><input type="button" id="btn1" value="delete"></div>
<script>
document.getElementById("btn1").onclick=function(){
  var tds=document.getElementsByTagName("td");
  for(var i=0;i<tds.length;i++){
   if(tds[i].innerHTML.indexOf("HAHA")>-1){
   tds[i].innerHTML="&nbsp;";
   }
  }
  }
</script>
</body>
</html>