Glad I could help.
There are three abilities that NPCs use: "vine_snare" (single target, this is the one the plant girls use), "action_grasping_vine_proj" (the one that has a forward moving fan-like projectile) and "boss_spreading_seeds" (the one, where multiple projectiles get thrown in the air and turn into vine_traps upon landing). First and second can be used by anyone, third one requires your hp to be at certain level to use (less than 75%, I think). None of them, if I remember correctly, have their respective skillbooks in the game by default.
If you want manuals for abilities, I can give you mine
MEGA, just ignore (or delete from the file) all the extra stuff that is not present in vanilla game. The game should tell you if you've learned an ability after reading a book, or either tell you that it doesn't exist.