Actually, it has happened with results that include hacker news discussions. I scrape through and expand EVERY comment on a 6 month old post and still find no partial or exact matches for my search keyword. It is very clear to me that Google has switched behavior. It used to flex on how awesome it was to bring you to an esoteric corner of the internet matching your exact query. Now, it tries to converge your queries into what it thinks you want(not what you asked for) and funnel you into large websites at the expense of utility.
Which can be incredibly frustrating if you know the problem well enough to need a different answer.
I also love when my search is narrow enough that Google instead starts to return more generic pages for totally different programming languages instead of the smaller result set that matches exactly. It is very easy to observe as you explore a topic. At some point, you got a wall where any increase in search specificity seems to yield worse results than queries that helped you get to that point.
Which... Why isn't Google learning that some users are constantly seeking out verbatim for results they'll click on and adjusting their search results to be more verbatim?