Searches the Google Ad Transparency Library for advertisers by name. Returns a list of matching advertisers with their name, advertiser_id, and region, plus a list of associated website domains. Use the returned advertiser_id to look up a company's ads. Defaults to US when region is not passed, so pass a 2-letter country code like AU or CA when searching for advertisers in another region. Uses the caller's OpenAny gateway credentials. Charges and authorization are determined by the gateway.