There's a genetic study showing how there was a wave of Austroasiatics from Vietnam which once immigrated to the Philippine before Austronesians came in, mixed with them and slowly displaced and replaced the Austroasiatics.
From this paper...
Multiple migrations to the Philippines during the last 50,000 years
https://www.pnas.org/content/118/13/e2026132118
The 2nd Migration Wave (Part B in the picture) were Austroasiatics from Mainland Southeast Asia, before Austronesians (Cordillerans) supplanted them.
Afterwards there was Austronesian/Philippine colonizing of Vietnam. Jade imported from Taiwan, sculpted in the Philippines, ended up in the markets of Hanoi.
https://www.researchgate.net/publica...an_Archaeology
Certainly the Sa Huynh Culture, the predecessors of the Champa Civilization in Central Vietnam were descended from Austronesian Borneans and Filipinos settling into Vietnam taking with them their green Jade from Taiwan.
https://en.wikipedia.org/wiki/Sa_Hu%E1%BB%B3nh_culture
South Vietnam is Austronesian Clay
Cham man come home, come home to Papa Philippines.