For example, just the other day I was searching for one string that I knew was part of a common code repository. To my surprise google couldn't find anything at all. Yandex on the other hand found the repository immediately and linked to github.
Other common issue with google is the difficulty of finding stuff like forum posts related to the search query. Sure, you could append "reddit" to the query, but there are still plenty of traditional forum sites and some of them have decades worth of discussion. I Never see those sites pop up on a typical google search unless I specifically look for them. Again, with yandex, my experience is much better, it is not uncommon to see posts from forums to be on the first page of results.