ive been trying non stop to get drool and spit to look realistic on zbrush but every material i’ve tried and altered just doesn’t give me the right effect. any tips or trick for water/liquid on zbrush 
You should investigate BPR Transparency. You can paint it then adjust the opacity to your liking. Fiddle with the sub surface scattering in the render palette/tab. A few youtube vids on this process. I wish there was a good water material or even beter a true glowing matcap. But alas much of that comes from 3rd party render engines like KeyShot or marmoset toolbag.