There’s just so many ingredients that can help, it takes experimentation.
You have the “herbs” (valerian, hops, lemon balm, lavender), then you have the “chemical compounds” (melatonin, phenibut, GABA, 5-HTP, glycine, magnesium).
I think the best stack is some kind of mix there, and it’s probably unique to you.
I’m boring and do well enough with a 200mg magnesium citrate tab. Falling asleep definitely not a problem for me lately!