Use sample :
<?php
require_once dirname(__FILE__).'/vendor/autoload.php';
$associateTag = '';
$awsAccessKey = '';
$secretAccessKey = '';
$app = new \NicolasMugnier\AdvertisingApi\App\Application();
// ItemLookup
$response = $app->getContainer()->get('itemlookup_client')
->setAssociateTag($associateTag)
->setAwsAccessKey($awsAccessKey)
->setSecretAccessKey($secretAccessKey)
->setResponseGroup('Offers')
->setCondition('All')
->setMerchantId('All')
->setItemId('B01FNC924E')
->setIdType(\NicolasMugnier\AdvertisingApi\ItemLookup::kTypeASIN)
->search();
echo $response->getBody();
// BrowsenodeLookup
$response = $app->getContainer()->get('browsenodelookup_client')
->setAssociateTag($associateTag)
->setAwsAccessKey($awsAccessKey)
->setSecretAccessKey($secretAccessKey)
->setBrowseNodeId('340856031')
->search();
echo $response->getBody();