Greek mati and Malay mata, eye
Nusa in Bali means islands. Looks very similar to Greek νήσος ‘island’.
German “Ach so” is quite similar to Japanese “A’ soo”, and it has the same meaning. The ‘ in the Japanese is a glottal stop, while the German ch is the famous “ach-sound”, but close enough.
The meaning is ‘Oh, I see.’
And indeed, “A'” means ‘Ach’, ‘Oh’ and “soo” means ‘so’ (both English and German).