In Monster Hunter World you must collect 10 Gajalaka Doodles for the quest “Cultural Exchange: Gajalaka Linguistics”. This quest is required to get the Meowlotov Cocktail gadget for your Palico.
The Gajalaka Doodles only show up during this one quest. If you go there without the quest you won’t find anything. You get this quest in Astera from the Lynian Researcher, after having found the first 5 Palico Gadgets. If you have not yet done this, please refer to this guide: Monster Hunter World All Palico Skills (Gadgets).
The problem is that the Gajalaka Doodles do not respawn so you can only pick them up once and they cannot be farmed. They are only found in specific locations that the game does not reveal to you. Generally, they are near Gajalakas, the red furry midgets scattered around high-rank maps. There are 1-2 doodles near them. When you switch on the endemic life filter on the map you can find the Gajalaka more easily.
Gajalaka Doodles only spawn on high-rank maps (6 Stars difficulty)!
This is what a doodle looks like (it will glow green like a monster track when you get close):
Gajalaka Doodle Locations
Note: The Green Circle marks the location in all screenshots.
There are 3 of them in this one cave.
There are 2 where the Gajalaka are standing (on the walls).
1 is found where the Gajalakas are at.
Here is 1 more.
Only 1 doodle in this spot.
Also 1 in this spot.
And this should be your 10th and final Gajalaka Doodle.
After you have collected 10 doodles, head back to the Lynian Researcher in Astera, the one who gave you the quest.