จะแยกการค้นหาจาก textbox กับ jumpmenu ออกกันยังไงคะ

<table width="100%" border="0"  align="center" cellpadding="3" cellspacing="1">
  <tr>
  <td width="518" style="font-size:16px; font-weight:bold;">รายชื่อผู้สมัครงานทั้งหมด</td>
  <td width="167" align="right">
 
 <!-- <form action="position_add.php" method="get" name="add">
<div align="center"><input name="" type="submit" value="add" style="cursor:pointer;" /></div>
</form>-->
  </td>
  </tr>
  <tr>
    <td style="font-size:16px; font-weight:bold;">&nbsp;</td>
    <td align="right">&nbsp;</td>
  </tr>
  <tr>
    <td style="font-size:16px; font-weight:bold;"><form name="frmSearch" method="get" action="<?=$_SERVER['SCRIPT_NAME'];?>" onsubmit="return validate();">
ค้นหาจาก ชื่อ-สกุล
      <input name="txtKeyword" size="30" type="text" id="txtKeyword" value="<?=$_GET["txtKeyword"];?>" >
      <input type="submit" name="imageField" id="imageField" value="ค้นหา"  />
    </form>
    
 <form>
<select name="jumpMenu" id="jumpMenu" onChange="MM_jumpMenu('parent',this,0)">
<option name="jumpMenu" value="">----แสดงข้อมูลในฐานข้อมูล--------</option>
<?
$strSQL ="select * from position";
$objQuery = mysql_query($strSQL);
while($objResult = mysql_fetch_array($objQuery)){
	?>
<option value="apply_all2.php?positionID=<?=$objResult["positionID"];?>" <?php if($_GET['jumpMenu'] == 'positionID'){ ?> checked="checked" <?php } ?>><?=$objResult ["position_name"];?></option>
<?
}
?>
</select>



</form>
    
    </td>
    <td align="right">&nbsp;</td>
  </tr>
</table>

<?

if($_GET["txtKeyword"] != "")
	{
	$strSQL = "SELECT * FROM application WHERE name LIKE '%".$_GET["txtKeyword"]."%'";
	}
	
else if($_GET["txtKeyword"] == "")
	{
	$strSQL = "SELECT * FROM application";
	}
	
else if($_GET["jumpMenu"] == 'positionID')
	{
	$strSQL ="SELECT * from application a left join position b on a.positionID=b.positionID where a.positionID='".$_GET ["positionID"]."' ";
	}
	
else if($_GET["jumpMenu"] == "")
	{
	$strSQL ="SELECT * from application";
	}


//$strSQL ="SELECT * from application a left join position b on a.positionID=b.positionID where a.positionID='".$_GET ["positionID"]."' ";


	
	$objQuery = mysql_query($strSQL) or die ("Error Query [".$strSQL."]");
	$objResult = mysql_fetch_array($objQuery);



$Num_Rows = mysql_num_rows($objQuery);

$Per_Page = 10;   // Per Page

$Page = $_GET["Page"];
if(!$_GET["Page"])
{
	$Page=1;
}

$Prev_Page = $Page-1;
$Next_Page = $Page+1;

$Page_Start = (($Per_Page*$Page)-$Per_Page);
if($Num_Rows<=$Per_Page)
{
	$Num_Pages =1;
}
else if(($Num_Rows % $Per_Page)==0)
{
	$Num_Pages =($Num_Rows/$Per_Page) ;
}
else
{
	$Num_Pages =($Num_Rows/$Per_Page)+1;
	$Num_Pages = (int)$Num_Pages;
}

$strSQL .=" Order By appID DESC LIMIT $Page_Start , $Per_Page";
$objQuery  = mysql_query($strSQL);

?>


<table width="100%" border="0" class="tbshow" bgcolor="#ccc" align="center" cellpadding="5" cellspacing="1">
  <tr>
    <td width="50" class="tbshowtr"><div>ลำดับ</div></td>
    <td width="250" class="tbshowtr"><div>ชื่อ-สกุล</div></td>   
    <td width="250" class="tbshowtr"><div>ตำแหน่ง</div></td>
    <td width="150" class="tbshowtr"><div>วันที่สมัคร</div></td>
    <td width="100" class="tbshowtr"><div>ดูใบสมัคร</div></td>
    <td width="100" class="tbshowtr"><div>เอกสาร</div></td>
  </tr>
  
 <?
$i=1;
if($Page > 1)
{
	$i = ($Per_Page * ($Page-1)) + 1; 
}
while($objResult = mysql_fetch_array($objQuery))
{



?>
<tr bgcolor="#fff">
<td><div align="center"><?=$i;?></div></td>
<td align="center"><?=$objResult["name"];?></td>
<td align="center"><?=$objResult["positionName"];?></td>
<td align="center"><?=$objResult["Creatdate"];?></td>
<td align="center"><a href="apply_detail.php?appID=<?=$objResult["appID"];?>"><img src="../../images/view_icon.png" border="0"></a></td>
<td align="center"><a href="../../file/<?=$objResult["resume"];?>"><img src="../../images/dl_icon.png" border="0"></a></td>
</tr>
 <?
		$i++;

}

?>
</table>