Need AGGREGATE to list when category is mixed up with others under one cell

Hello, I have a Data-Validation Drop Down on Cell A1 that contains Board Game Categories and whenever I click them, I need excel to pull all the Board Games associated with that category and list them down in COLUMN A. So far, my code is only pulling Board Games that has that specific category name singled out in one cell [see purple text in image]. I need excel to also pull Board Games when the category name is mixed up with other different category names under one cell [see red text in image].

This is the code on Cell A2, that I would appreciate any kind of help I can get with to get it to work. Thank You.
=INDEX($C$2:$C$156,AGGREGATE(15,6,(ROW($D$2:$D$156)-ROW($D$2)+1)/($D$2:$D$156=$A$1),ROWS(A$2:A2)))

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