The specific phrasing of your query ("download fixed 18... better") is highly characteristic of links found on unofficial file-sharing sites. Be extremely cautious, as these types of download titles are often used to mask malware, adware, or phishing scams
The original 2008 rips floating online had notorious issues: download fixed 18 dog world 2008 unrated english better
Because Dog World has no rights holder actively selling it, you cannot buy it on Amazon, iTunes, or Netflix. Some obscure DVD-R copies appear on eBay occasionally, but those are likely bootlegs. The specific phrasing of your query ("download fixed 18