No real surprise.
Asians,as a general rule tend to work harder and longer than other ethnic groups,plus they tend to stick together and pool the family income,rather than the typical "bleep YOU,ME first!" attitude of other ethnic groups. Including whites.
They then tend to take this money and spend it on investments as well as furthering their educations,instead of on bling or comfort items for selves. Which is itself an investment in the future.
This ain't what anyone would call "secrets".