ESSENCE OF WISDOM - HOW TO GET A LOT

Actually i am on floor 3 but i have see that the only way to get Essence of Wisdom is finish a Exp lv and i got 5 !!
But when i finish all Exp lv , how i can got essence of wisdom ??
Exp lv reward is 5 essence but 40 energy is much for try to farm essence.
What strategy do you use for have a lot of essence ??
I have try to DE the skill book, but exp skill book now is so rare to found that are not good strategy farm it.
Thanks all

TLT is heavely a farming game, the only way to get alot is saving the gold coins, so when you find an advanced skill book in exp you can respin until you get it, and then DE it, if its an unneeded skill.

allso you get 5 or 10 a week as i recall for log in bonus.