Filter paper

What is the best filter paper to run in Buchner? I have stuff getting through mu Chinese paper when winterizing

What micron is the paper you are currently using?
What is making it past your papers? wax or powders?
Tell us about your method for putting the paper in the funnel, are you wetting it? are you cutting it to size or letting it fold and crease around the edge?

I am not sure, it is some Chinese paper with no indication of micron size, If I were to guess, I would say Whatman #1 equivalent.
Wax
It is precut circles the size of the funnel and sits flat. Wetting with ethanol pre filtering