Qwant, Ecosia, and (to an extent) DDG share the same Bing backend for web results, so if you're particularly interested in trying out alternatives, here are some others. All of these have their own search indexes.
https://yippy.com - ugly, but probably the best independent search engine outside the "big ones" and DDG
https://private.sh/ - Run by PIA as a proxy for Gigablast, small index but rapidly getting better
https://beta.cliqz.com - German based, their technical blog has been posted frequently on HN. Will eventually require a browser extension or their own browser to search.
https://yandex.com - Ought to be mentioned, but certainly not privacy focused.
https://yippy.com - ugly, but probably the best independent search engine outside the "big ones" and DDG
https://private.sh/ - Run by PIA as a proxy for Gigablast, small index but rapidly getting better
https://mojeek.com - UK-based, worth trying but has a spam problem
https://beta.cliqz.com - German based, their technical blog has been posted frequently on HN. Will eventually require a browser extension or their own browser to search.
https://yandex.com - Ought to be mentioned, but certainly not privacy focused.