สอบถามเรื่องการใช้ session และ $pdo->seach รบกวนช่วยดูให้หน่อยครับ

$str = $pdo->seach($_SESSION['user'],md5($_SESSION['pass']));
	if($str->rowCount() != 0)
	{
	header("Location:wecome.php");
	}
	Else header("Refresh:1;url=work1.php");
	}
?>

<?php
session_start();
if(!isset($_SESSION['user']))
{
	header("Location:work1.php");
}
if(isset($_POST['submit']))
{
	//include("Class_Connection.php");
	include("Class_User.php");
	$name = trim($_POST['addname']);
	$pass = md5(trim($_POST['addpass']));
	$user = new User();
	if($user->insert($name,$pass))
	{
		echo "Insert Completely";
	}
	else echo "Insert Error";
}
?>

<?php
include("Class_Connection.php");
class User
{
	private $id;
	private $name;
	private $pass;
	private $pdo;
	public function __construct()
	{
		$this->pdo = MyDBConnection::getConnection("mysql");
	}
	public function insert($name,$pass)
	{
		$sql = "INSERT INTO USER(user,pass) VALUES(?,?)";
		//$pdo = MyDBConnection::getConnection("mysql");
		$stm = $this->pdo->prepare($sql);
		$stm->bindParam(1,$name);
		$stm->bindParam(2,$pass);
		if($stm->execute())
		{
			return true;
			//echo "New User with id : ".$this->pdo->lastInsertId()." added.\n";
		}
		else
		{
			return false;
			//echo "ERROR : ".print_r($this->pdo->errorInfo());	
		}
	}
	public function seach($name,$pass)
	{
		$sql = "SELECT * FROM USER WHERE USER = ? AND PASS = ?";
		$this->pdo = MyDBConnection::getConnection("mysql");
		$stm = $this->pdo->prepare($sql);
		$stm->bindParam(1,$name);
		$stm->bindParam(2,$pass);
		$stm->execute();
		return $stm;
	}
	public function ShowAll()
	{
		$sql = "SELECT * FROM USER";
		$str = $this->pdo->query($sql);
		$str->execute();
		return $str;
	}
}
?>