How to dye artificial hair?

I recently conducted an experiment on dyeing natural tresses from goat hair.

In this video, I will be trying to dye artificial hair purchased from a craft store. Such hair looks good. You can see how to attach it to a doll’s head, it in a video tutorial on attaching tresses.

The experiment uses improvised dyes that I found at home: various paints, felt-tip pens, and so on.

The process is quite fascinating, but the result surprised me, most of the paints were washed off, as if they were not there. How can you give a shade to such hair at home, see in the video.

If you know other ways to dye doll hair, please write in the comments.