App Search - How to add "multi field", a field with array of values (like color)

Question

I am trying to use App Search, and when I index a document that looks like:

name: 'metalica t-shirt'
colors: ['red', 'black']

The engine removes 'black' and leaves it as:

name: 'metalica t-shirt'
colors: 'red'

But I want it to appear both under 'red' color and 'black' color filter on Search UI, is it supported?