https://app.rakuten.co.jp/services/api/IchibaItem/Search/20220601?applicationId=b81babe0dea9170ecdaf3c019d8709b6&affiliateId=0433111a.0d75cb85.0433111b.a7f1907e&keyword=%E3%82%B7%E3%83%81%E3%83%AA%E3%82%A2%E7%94%A3%E3%83%9E%E3%82%B0%E3%83%AD%E3%81%AE%E3%81%8B%E3%82%89%E3%81%99%E3%81%BF%E3%83%AA%E3%83%B3%E3%82%B0%E3%82%A4%E3%83%8D+%E3%83%AC%E3%83%A2%E3%83%B3%E9%A2%A8%E5%91%B3&format=json&formatVersion=2&hits=5&page=1&sort=standard

URL_rss=XMLを見てみる。

stdClass Object
(
    [GenreInformation] => Array
        (
        )

    [Items] => Array
        (
        )

    [TagInformation] => Array
        (
        )

    [carrier] => 0
    [count] => 0
    [first] => 0
    [hits] => 0
    [last] => 0
    [page] => 1
    [pageCount] => 0
)