DuckDuckGo is just Yahoo. I think the results are something like 99.9% the same, so whatever is the 0.1% they add, when I did the search, it results in maybe a slight difference in link ordering.
The reason it finds the "right" results is also the same reason its results are such garbage. And this is coming from someone whose default search is DuckDuckGo.
Whenever people complain about DDG's search results I am always a bit baffled. It works 95% of the time for me and that 5% is occurs when I am searching for the answer to some obscure bug. I know this is your word against mine but "garbage" is a bit of an exaggeration.
I think these are a majority of my searches, hence I had to switch back to google as DDG was almost never finding me any relevant result.
One really annoying thing is that python searches keep surfacing the python2 official docs instead of the python3 ones.
Ddg is my main search engine, but I find I fall back to g! queries more and more often.
I still prefer my Bing results without personalization, so I use DDG.
(Not to mention the right side "Answer box" that throws me off a bit since that result is not on the list of links)