It won’t matter how much light you add if you do not address that thrip issue. It will become ab infestation if it is nit already. Check underside of leaves with magnifier. You are looking for tiny, tiny movement from translucent orange / white translucent buds. Those are what are eating your leaves, stressing your plant, and reducing the health pf your plants.
Thrips. You can treat them in flower in a way that doesn’t compromise the health and quality of your flower. Conversely, there are ways you can treat them and poison your product...so choose wisely. You are what you smoke as
@organoman loves to say.
Good luck