I would say any topic that isn't covered by stack overflow tends to start bleeding badly. Now that GitHub has prevented searching source I am having less success searching for error messages, as I used to be able to extract the static string and land in source. For go specifically how many times are you landing on search results that aren't gotour, stack overflow, and go docs? If stack overflow was not so gracefully indexable things would fall apart pretty quick and in lots of areas it does.
I would say searching for businesses outside major metro areas has gotten increasingly bad. I had a situation in the last few months that a business would only appear when they were open (barbershop) but if they were off that day they were not even on page 3.
Finding materials suppliers local to you has been a nightmare, I've been resorting to Yahoo-grade business directories to actually find businesses. These are places where Google has them on their maps but they never return in search unless I force my location to be away from home. Historically I never had to do this kind of manipulation.
I am having better luck driving around or hand scrolling around maps to find places then I am with search at times. It feels like after the first ten results Google completely gives up. E.g. I look for lumber yards and I get 20 ace hardwares and maybe two of them are actually lumber yards, but it completely misses some local sawmills that are specialized and amazing
I am whiffing Chinese restaurant near this town, state. I know the place is there but I cant remember the name, I can find it manually on the map.