I take San dr feel good which has a good blend of nootropics, but on top of that I take choline, alcar and vinpocetine which I definitely notice a difference with. I've been here on my phone for 3 hours reading about nootropics and haven't gotten distracted yet

a little bit of caffeine can be great too, and I always chew a little nicotine gum during tests. If your an ex smoker (like me) be careful with that one.
I'm going to add piracetam and pramiracetam next and see what that does. I'm curious about ashwagandha cut don't know enough about it to give it a try, but certain studies suggest it could make me feel awesome