I don't know what is wrong is am I just missing something, all my expected data is successfully receive based on firebug' console tab the problem is displaying the data.

Here's my jquery code:

success: function(data){
            var toAppend = '';
            if(typeof data === "object"){
                for(var i=0;i<data.length;i++){
                    toAppend += '<tr><td colspan="2">'+data[i]['main-asin'][0]+'</td></tr>';
                    toAppend += '<tr><td>'+data[i]['sub-asin'][0]+'</td><td></td></tr>';
                }
                $('.data-results').append(toAppend);
            }
        }

Here's my php code:

    foreach($xml->Items->Item as $item){
    $items_from_amazon[] = array('main-asin'=>$item->ASIN);
    foreach($xml->Items->Item->Variations->Item as $item){
        $items_from_amazon[] = array('sub-asin'=>$item->ASIN);
    }
}

echo json_encode($items_from_amazon); //return amazon products

And here's the result from my firebug: