How to get parts in part, excluding parts that are only touching

[MrTatom]

I have a model and it’s primary part is an hitbox. I need to detect what parts are inside of the hitbox. I can easily do it using game.Workspace:GetPartsInPart(hitbox) but it will include parts that are only touching the hitbox and not necessarily inside of the hitbox. I need to filter out those parts that are touching the hitbox but not necessarily inside of it.

How can I get ONLY parts that are inside the hitbox WITHOUT parts that are only touching the hitbox and not necessarily inside of it?

[Forummer]

https://developer.roblox.com/en-us/api-reference/function/WorldRoot/GetPartBoundsInBox