like mentioned above, you need to get familiar or check the possible rolls, per affix incase you have one of the same pool, like vuln i think was mentioned, so this means you would never get the one you want. So until you know, check the possible rolls, its a little red icon top right side of the menu on the occultist.
Or you could go for a temper, crit damage. or gems. board nodes, depends what you are after i guess.