Cart promotion by applying a limit on the qualifying products

Hello Experts,

I am looking for possible approaches by which we can achieve limiting the cart entries (qualifying products) on which promotion can be applied in Hybris 2011 version.

CONDITION - Qualifying products - Product A, Product B, Product C, Product D
ACTION - Fixed 100 discount on product

CART contains Product A, Product C and Product D that qualify for the promotion

OOTB - Applies product discount on all products (i.e. Product A, Product C and Product D)

How can I achieve to apply product discount only on first two products i.e. Product A, Product C

Is there any way to achieve using OOTB or do we need to customize the condition/action?

Appreciate any responses here.

Thanks