Yeah DDG has always been weirdly evasive about how their search engine works and where results are coming from. If it makes you feel any better, bing has been c

Yeah DDG has always been weirdly evasive about how their search engine works and where results are coming from. If it makes you feel any better, bing has been caught copying results from Google (https://www.wired.com/2011/02/bing-copies-google/ https://www.wired.com/2011/02/bing-copies-google/) so there's a chance you'll get bing results plus results from whatever other search engine bing copies. Personally, I don't even mind if using DDG is the same thing as searching bing so long as it actually works, but they still can't get a simple search like "office -microsoft" or "headphones -best" right. I even thought they acknowledged the problem and were looking into it at one point.