$sales = array();  // creating a blank array

$query = "SELECT * FROM `sales_details` ORDER BY `sales_id` ASC";  // setting up a query to get all the sales

$result = mysql_query($query);  // running the query

$i = 0;  // we will be needing a counter;

while ( $row = mysql_fetch_array($result) ) {  // we process the sales one by one

$sales[i] = array();

$sales[i]['sales_id'] = $row['sales_id'];

$product = $row['product_id'];
$query = "SELECT `productname` FROM `sales_products` WHERE `product_id` = $product";  // let's get the product
$product_result = mysql_query($query);
$sales[i]['product_id'] = mysql_result($product_result,0,'productname');

$user = $row['fromuser'];
$query = "SELECT `name` FROM `sales_users` WHERE `user_id` = $user";  // let's get one user
$user_result = mysql_query($query);
$sales[i]['fromuser'] = mysql_result($user_result,0,'user_id');

$user = $row['touser'];
$query = "SELECT `name` FROM `sales_users` WHERE `user_id` = $user";  // let's get the other user
$user_result = mysql_query($query);
$sales[i]['touser'] = mysql_result($user_result,0,'user_id');

$i++

}

foreach ($sales as $one_item) {

// here you can print out everything you need, since it's all stored in $one_item[]

}

$query = "
SELECT sales_details.sales_id, sales_products.productname, sales_users.name as namefrom, s.name as nameto
FROM sales_details
left join sales_products as sales_products on (sales_products.product_id = sales_details.product_id)
left join sales_users as sales_users on (sales_users.user_id = sales_details.FromUser)
left join sales_users as s on (s.user_id = sales_details.ToUser)
ORDER BY sales_id ASC";
$result = mysql_query($query);  // running the query
echo "<strong>id - product - from - to</strong>";
while ( $row = mysql_fetch_array($result) ) {
echo $row["sales_id"] . " - " . $row["productname"] . " - " . $row["namefrom"] . " - " . $row["nameto"] . "<br />";
}