https://app.rakuten.co.jp/services/api/IchibaItem/Search/20220601?applicationId=b81babe0dea9170ecdaf3c019d8709b6&affiliateId=0433111a.0d75cb85.0433111b.a7f1907e&keyword=%E3%83%9E%E3%82%A4%E3%83%A4%E3%83%BC+%E3%83%87%E3%82%A3%E3%82%BA%E3%83%8B%E3%83%BC%E3%83%A2%E3%83%8E%E3%82%AF%E3%83%AD%E3%83%BC%E3%83%A0%E3%82%B3%E3%83%AC%E3%82%AF%E3%82%B7%E3%83%A7%E3%83%B3+20cm+%E3%83%95%E3%83%A9%E3%82%A4%E3%83%91%E3%83%B3&format=json&formatVersion=2&hits=30&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
)