Как я могу получить нужные мне поля из XML ответа

Я пытаюсь получить продукты от Amazon, но реакция Amazon — XML.
Как я могу получить поля, которые мне действительно нужны, без получения других полей.

Вот мои коды:

<?php
date_default_timezone_set('UTC');

$url = 'https://mws.amazonservices.com/Products/2011-10-01';

$data = array(
'Action' => 'ListMatchingProducts',
'SellerId' => '************',
'MWSAuthToken' => 'amzn.*************************',
'AWSAccessKeyId' => '******************',
'Timestamp' => date("Y-m-d\TG:i:s\Z"),
'Version' => '2011-10-01',
'MarketplaceId' => '************',
'SignatureVersion' => '2',
'SignatureMethod' => 'HmacSHA256',
'Query' => 'hunger games'
);

ksort($data);
$QueryString = http_build_query($data,'','&',PHP_QUERY_RFC3986);

$stringToSign =
"POST\n".
"mws.amazonservices.com\n".
"/Products/2011-10-01\n".
$QueryString;

$secret = 'secret*******************************';
$signature = hash_hmac('sha256', $stringToSign, $secret, true);

$data['Signature'] = base64_encode($signature);
ksort($data);


$options = array(
'http' => array(
'header'  => "Content-type: application/x-www-form-urlencoded\r\n",
'method'  => 'POST',
'content' => http_build_query($data),
),
);

$context  = stream_context_create($options);
$result = file_get_contents($url, false, $context);



$p = xml_parser_create();
xml_parse_into_struct($p, $result, $vals, $index);
xml_parser_free($p);
echo "<PRE>";
echo "Index array\n";
print_r($index);
echo "\nVals array\n";
print_r($vals);

Это вывод …
Ребята Помогите мне получить вывод, который мне нужен, например, productname, ASIN, imageURL ..

[LISTMATCHINGPRODUCTSRESPONSE] => Array
(
[0] => 0
[1] => 777
)

[LISTMATCHINGPRODUCTSRESULT] => Array
(
[0] => 1
[1] => 773
)

[PRODUCTS] => Array
(
[0] => 2
[1] => 772
)

[PRODUCT] => Array
(
[0] => 3
[1] => 61
[2] => 62
[3] => 148
[4] => 149
[5] => 192
[6] => 193
[7] => 246
[8] => 247
[9] => 365
[10] => 366
[11] => 448
[12] => 449
[13] => 498
[14] => 499
[15] => 598
[16] => 599
[17] => 714
[18] => 715
[19] => 771
)

[IDENTIFIERS] => Array
(
[0] => 4
[1] => 9
[2] => 63
[3] => 68
[4] => 150
[5] => 155
[6] => 194
[7] => 199
[8] => 248
[9] => 253
[10] => 367
[11] => 372
[12] => 450
[13] => 455
[14] => 500
[15] => 505
[16] => 600
[17] => 605
[18] => 716
[19] => 721
)

[MARKETPLACEASIN] => Array
(
[0] => 5
[1] => 8
[2] => 64
[3] => 67
[4] => 151
[5] => 154
[6] => 195
[7] => 198
[8] => 249
[9] => 252
[10] => 368
[11] => 371
[12] => 451
[13] => 454
[14] => 501
[15] => 504
[16] => 601
[17] => 604
[18] => 717
[19] => 720
)

[MARKETPLACEID] => Array
(
[0] => 6
[1] => 65
[2] => 152
[3] => 196
[4] => 250
[5] => 369
[6] => 452
[7] => 502
[8] => 602
[9] => 718
)

[ASIN] => Array
(
[0] => 7
[1] => 66
[2] => 153
[3] => 197
[4] => 251
[5] => 370
[6] => 453
[7] => 503
[8] => 603
[9] => 719
)

[ATTRIBUTESETS] => Array
(
[0] => 10
[1] => 49
[2] => 69
[3] => 128
[4] => 156
[5] => 189
[6] => 200
[7] => 243
[8] => 254
[9] => 345
[10] => 373
[11] => 428
[12] => 456
[13] => 495
[14] => 506
[15] => 586
[16] => 606
[17] => 694
[18] => 722
[19] => 763
)

[NS2:ITEMATTRIBUTES] => Array
(
[0] => 11
[1] => 48
[2] => 70
[3] => 127
[4] => 157
[5] => 188
[6] => 201
[7] => 242
[8] => 255
[9] => 344
[10] => 374
[11] => 427
[12] => 457
[13] => 494
[14] => 507
[15] => 585
[16] => 607
[17] => 693
[18] => 723
[19] => 762
)

[NS2:ACTOR] => Array
(
[0] => 12
[1] => 13
[2] => 14
[3] => 15
[4] => 16
[5] => 17
[6] => 18
[7] => 158
[8] => 202
[9] => 203
[10] => 204
[11] => 205
[12] => 206
[13] => 207
[14] => 208
[15] => 209
[16] => 210
[17] => 211
[18] => 256
[19] => 257
[20] => 258
[21] => 259
[22] => 260
[23] => 261
[24] => 262
[25] => 263
[26] => 264
[27] => 265
[28] => 458
[29] => 459
[30] => 460
[31] => 461
[32] => 462
[33] => 463
[34] => 464
[35] => 508
[36] => 509
[37] => 510
[38] => 511
[39] => 512
[40] => 513
[41] => 514
[42] => 515
[43] => 516
[44] => 517
[45] => 608
[46] => 609
[47] => 610
)