yes they are hard to find..my first bud i harvested had the most damage and went through a lot of my other bud and found those tiny fuckers in some of the tips...the bud can be rescued if found early but you must keep moths/butterflies from landing on your plant.
there are some moth traps out there at like homedepot/lowes. I would also recommend using a mosquito net like the one below...although its quite late now to start using this, i would recommend every outdoor grower use these going forward...they work better on shorter plants (indica) because they aren't very long in height. i might consider doing a double layer just to be safe. They are mesh so light/air will go in and keep the bad bugs out..you can even but ladybugs or other beneficial bugs (trichogamma wasps for killing catepillar eggs) in with this too!!
I also would suggest that you go through every single bud especially the tips. you'll have to bend back the buds on your colas to see whats going on... i don't think any foliar could penetrate that deep...highly impossible. i'm doing this and its no easy task...very time consuming...make sure you under a bright light because newly hatched worms are hard to see but you've gotta find them or else.
I never hated butterflies and moths so much until now!!