I think you should take a photo of her and post it up( she might be a lost dog since you said its maintained well) and is it only one pup or a litter of pups? Normally a medium breed (since u said GD mixed) would have 4 or 5 at least. So I would think that its either the uncle or someone took it. Well should be best if you asked the uncle if he is owning it, if not take her to the nearest shelter, if you cant do that then here's a link that might help.
You should contact MDDB (MALAYSIAN DOGS DESERVE BETTER), this is their facebook account :
https://www.facebook.com/MalaysianDogsDeserveBetter
Take a pic of both the mom and pup and write some details and post.
=) good luck