Goblin's Phlegm is the name of the potion.
Lol, its not actual Goblin's Phlegm, its just the name, as far as i know (the main ingredient is a herb i think).
Tho this just adds to how bad at naming the characters are. The name just gives a really bad image so their sales are bad, among other things (づ￣ ³￣)づ
Humans like making stuff from weird stuff
Gelatin/collagen is made of animal cartilage skin and bones
And ambergris also used in the parfum industry is basically whale puke
Can't get over how the characters casually research goblin's phlegm for potions. Granted, there are worse "ingredients" in other mangas, manhwas, manhuas and irl, it still makes me gag.
Random fact: Apparently irl, musk is extracted from a deer's certain organs. So maybe the author is going for a similar approach for medicine in this story.