dedecms织梦怎么给后台管理员列表增加搜索功能

<form action="sys_admin_user.php" name="form1" method="get">
      <table border="0" cellspacing="0" cellpadding="3">
      <tr>
          <td>管理员搜索：</td>
          <td><input name="keyword" type="text" id="keyword" size="12" style="width:120px" value="{dede:global name='keyword'/}" /></td>
          <td><input name="imageField" class="np" type="image" src="images/button_search.gif" width="60" height="22" border="0" /></td>
        </tr>
      </table>
      </form>

else $rank = " WHERE CONCAT(dede_admin.usertype)='$rank' ";

if(!isset($keyword)) $keyword = '';
else $keyword = trim(FilterSearch($keyword));

if($keyword<>'')
{
$query = "SELECT dede_admin.*,dede_arctype.typename FROM dede_admin LEFT JOIN dede_arctype ON dede_admin.typeid = dede_arctype.id $rank  where userid LIKE '%$keyword%' OR uname LIKE '%$keyword%'";
}
else
{
$query = "SELECT dede_admin.*,dede_arctype.typename FROM dede_admin LEFT JOIN dede_arctype ON dede_admin.typeid = dede_arctype.id $rank ";
}