Some conditions of discount, for a number of product purchases

Hello, this is a great plugin.

I want to ask.
I made a case discount: buy a certain amount for a certain category or tag. This can be accomplished by using the rules in setting the discount “if the order item count”

If there is more than one condition:
1. If you buy a total of 3 products, then get a discount of 10%
2. If you buy a total of 7 products, then get a discount of 20%
3. If you buy a total of 15 products, then get a discount of 30%

Whether this can be achieved using this plugin?

I tried, but when the condition number 2 are met. Discounts condition that occurs is still the number 1.

Any ideas on this?

Is multilevel discount (for the amount of product) allows?

Sorry if my English is bad. I hope you understand.
Thanks.