$keyword   = $_GET['keyword'] ?? '';
$module    = $_GET['module'] ?? '';
$location  = $_GET['location'] ?? '';
$experience= $_GET['experience'] ?? '';

$sql = "SELECT * FROM jobs WHERE 1=1";

if(!empty($keyword)){
    $sql .= " AND (job_title LIKE '%$keyword%' 
              OR skills LIKE '%$keyword%')";
}

if(!empty($module)){
    $sql .= " AND sap_module='$module'";
}

if(!empty($location)){
    $sql .= " AND location='$location'";
}

if(!empty($experience)){
    $sql .= " AND experience='$experience'";
}