<script language="javascript">
function onChangeKey2() {

var wr_1 = document.fsearch_area.wr_1.value;
var wr_2 = document.fsearch_area.wr_2.value;
var wr_3 = document.fsearch_area.wr_3.value;
var wr_4 = document.fsearch_area.wr_4.value;

document.fsearch_area.stx.value = wr_1 + " " + wr_2 + " " + wr_3 + " " + wr_4;
document.fsearch_area.submit();

}
</script>
<div class="board_search">
<form name=fsearch_area method=get>
<input type=hidden name=bo_table value="<?=$bo_table?>">
<input type=hidden name=sca value="<?=$sca?>">
<input type=hidden name=sop value="or">
<input type=hidden name=sfl value="wr_1||wr_2||wr_3||wr_4">
<input type=hidden name=stx value="">
<tr>
    <td>
<select name="wr_1">
        <option value="">전체</option>
<?
$sql1 = "SELECT * FROM g4_write_$bo_table ";
$result1 = mysql_query($sql1);

for($i = 0; $i < $data=mysql_fetch_array($result1); $i++){
?>
<option value="<?=$data[wr_1]?>"><?=$data[wr_1]?></option>
<?
}
?>
        </select>

<select name="wr_2">
        <option value="">전체</option>
<?
$sql1 = "SELECT * FROM g4_member ";
$result1 = mysql_query($sql1);

for($i = 0; $i < $data=mysql_fetch_array($result1); $i++){
?>
<option value="<?=$data[mb_name]?>"><?=$data[mb_name]?></option>
<?
}
?>
        </select>
<select name="wr_3">
        <option value="">전체</option>
<?
$sql1 = "SELECT * FROM g4_member ";
$result1 = mysql_query($sql1);

for($i = 0; $i < $data=mysql_fetch_array($result1); $i++){
?>
<option value="<?=$data[mb_name]?>"><?=$data[mb_name]?></option>
<?
}
?>
        </select>
<select name="wr_4">
        <option value="">전체</option>
<option value="처리중">처리중</option>
<option value="처리완료">처리완료</option>
<option value="전달">전달</option>
        </select>
<input type="image" src="<?=$board_skin_path?>/img/btn_search.gif" border='0' align="absmiddle">
    </td>
</tr>
</form>
</div>



이런식으로 여유 필드로 셀릭트바를 이용해서 검색을 하려고 합니다.

and가 아닌 or로 그 값이 딱 맞는 것만 나오게 하려고 합니다.

근데 stx값이 걍 "" 로 하면 걍 작동을 안하는거 같은데......

고수님들 도움 좀 주세요