从其他网站获取搜索数据

Is there a way to capture search data from other websites? For example, if a user visits any website with a search field, I am interested in what that user types into that search field to get to the desired blogpost/webpage/product. I want to know if this is possible by scraping the site, or by any other means. Also, is it illegal to perform a scraping operation to record such data on a third party website? Also, if this is possible using PHP and Python? Is there a way to capture search data from othe