I try to use DuckDuckGo by default, but I have to switch to Google very often to get decent results.

This is constantly improving and if you have any relevancy issue examples you can always reach out (adam@duckduckgo.com).

Also if we're your default you can always use !g to forward a search to encrypted.google.com if the results don't meet your needs. In fact you can forward your search to over 6000 sites (https://duckduckgo.com/bang) and even suggest your own bangs :)