You need to start hitting those ruins. Anything that's a lab and got mechanical spiders will definitely have them. But also, Flats Lagoon and the towns near it sell them. Edge of the World sells a bunch. And the vendors in the skeleton capitol Black Desert City have them. Just venture forth, build up your crew, and start taking risks. The more dangerous the spot, the higher chance of advanced schematics, red engineering schematics, ai cores, etc. The game really makes you work for it, but it works out :) Flats Lagoon, Black Desert City, and End of the World should get you a couple dozen. But keep in mind each schematic costs $5000 cats, so you gotta pay up if you want to go the vendor route first.

Thanks! That helps a lot.