Are you playing on a new world or an old one?
Dayquil and nyquil both used to be some sort of undefined powder, and they were recently changed to liquids. If the instances you’re finding were generated prior to the change they won’t be in bottles so you won’t be able to pick them up. In that case all you should have to do is wander a bit until you come to a portion of the map that hasn’t been generated yet and you’ll find them properly spawned in containers.
If you’re playing on a new world and seeing this, then it’s a bug.
