The purpose of the built in behavior rules is to provide for discounts or addition of products into the shopping cart. When you create a behavior rule, you may find the need to check for multiple products in the shopping cart. For example,

1) [QtItems/C01=product1]>0 - will return true if product1 is in the shopping cart.

2) ([QtItems/C01=product1 or C01=product2]>0) - will return true if either product1 or product2 is in the shopping cart.

3) ([QtItems/C01=product1]>0) | ([QtItems/C01=product2]>0) - will return true if either product1 or product2 is in the shopping cart (same as #2).