DNA tests?

At least 2 companies have DNA tests with offers ending soon. My daughter in law did one a few years ago and was disappointed to see no mention of her Vietnamese roots a few generations back. And no I don’t think she had a different father as a result of an affair! Her daughter looked very Vietnamese as a young girl.

I am wondering if anyone has experience of these tests?

DNA memories? - NOT amateur radio

It is well known that physically characteristics can be passed down the generations. As an example, my brother-in-law looks just like a relative from 100 years ago.

Years ago I met a distant relative who branched away from our family tree in the 1700s. He looked remarkably like my uncle! That was over 200 years ago!

Now, I am no human biologist, but I gather much of our DNA is not used to create us physically. So, I wonder what it is for? Will we ever find out? Do we have hidden in our DNA, ancient memories? Maybe one day we will find out.