[contravariant]

Just set it as the default and just add !g to the end of your search query if you don't find what you're looking for to try the same query on google. Eventually you'll figure out which queries work better on which search engine.

In my experience duckduckgo tends to behave more like how google used to work, so if you pick a few well chosen keyword you tend to find stuff pretty quickly but it doesn't respond too well to ambiguous terms or full sentences, google is better at those.