You can't use EX1_164a or EX1_164b, because you don't play this card from your hand.
I have added to rule new parameter "owncarddraw" (extra carddraw on your turn).
You can use any comparison operators (=, !=, >, <)
You can use it separately or together with other parameters.
Examples:
1)Give a small bonus if your carddraw this turn more than 2:
owncarddraw>2,bonus=10
2)Give a small bonus if your carddraw this turn more than 2 and you have played Nourish:
p=EX1_164&owncarddraw>2,bonus=12
3)Give a negative bonus if your carddraw this turn less than 3 and you have played Nourish and you have less 4 cards in your hand: (don't forget that the rules work at the end of the turn, after all actions)
p=EX1_164&owncarddraw<3&ohc<4,bonus=-20