I'm really not trying to be an ass, but if I go to "bing.com", type "test", press "enter". I don't see "advanced" anywhere. The closest I see is a 'gear' that takes me to a completely different page that is not an advanced search.
You have the international version (like I do in Australia). The new design doesn't seem to have an advanced link anywhere (you can try it by going to preferences, and choosing 'Change country/region'.
Like, I ctrl+f'd to make sure I'm not just blind.