Aha, I see. The "View H" setting in the cog does not sync to your account, but is local.
I was reading it on my phone, and continued reading it on my PC (using the "tabs from other devices" function), but when I left the chapter I was reading, it had all vanished as far as I could see! It didn't even come up in search!
Of course, that was because the "View H" setting was set to "Hide". This behavior is very confusing! It might be better if there is at least a message saying "your search found H content that is hidden by your settings" or similar. (Or if there was an option to sync the View H setting to your account, hehe.)
Thanks!