Optimizing on all purchases trains Meta toward whoever converts cheapest and not necessarily the products you want to grow. Your Emfas data already defines which products matter: by category, margin tier, brand, or collection. Turn that catalogue enrichment into a training signal for Meta's algorithm to find buyers of the products worth selling more of.

Create a custom Purchase event and filter it on a Emfas product metafield (such as category = "Premium Collection" or margin tier = "High") so it only fires when an order contains those products.

Set the new event as your campaign's optimization goal, and Meta builds its audience model on buyers of your target products instead of all purchasers.
Emfas syncs product catalogue attributes to Shopify as metafields, so Littledata can read and turn them into a conversion signal. The fields you can build a campaign around:
| Data point you can target |
|---|
| Product attributes |
| Product taxonomy |
| Product information |
