Sometimes when you search something software releated in DDG you get an Stackoverflow instant answer. The problem is that these instant answers often are completely off-topic (for example when a search term is an example string in the SO post e. g. "münchen" - that's a city!) or only somewhat releated to the search (e. g. "PyQt 5"). In the description of instant answers it says they should be better than normal search results, but the Stackexchange results usually are often not, so maybe you should just disable them.
I'm sorry if my english isn't very good