[rules-users] Intersecting two collections in LHS

I have in the working memory all possible sentences that can be presented to the user ( class Sentence() ). Each sentence holds a collection (String collection) called descriptor that describe the sentence. Based on various rules I populate a collection called messageFilter which will be used to select the appropriate sentence. The proper sentence is one that all its descriptors match the one in the messageFilters What I would like is something of the sort: $sentences: ArrayList() from collect (Sentence(descriptor contains messageFilter) as messageFilter is a collection, this is not a valid code. What would be the proper method to implement it. I am using drools 5.1.1 but am willing to upgrade to 5.2 if required. Thanks, Hezi