Hi Alex,
To add on to the previous answer: any values that you filter by in Vision API Product Search must be added on the products in the index by you — i.e. the example of filtering by color would not work out of the box. You could, for instance, use Image Properties feature in Vision API
https://cloud.google.com/vision/docs/detecting-properties to precompute dominant colors for the product images.
In general, Vision API Product Search does take both color and pattern into account when ranking results, but does not provide a way to control the strength of color vs. pattern information in the ranking.
Best,
clayton