About Hong Kong retirement financial planning,

there is a couple - mr and mrs wong, income is HKD38000 and HKD 32000.

Both of them are entitled to receive a year-end bonus equivalent to 1-2 month's salaries depending on the profit figures of their employers.

Assume that they start work at 20 years old and they prefer retirement at the age of 65 and their aim is to have sufficient savings to support their living after retirement. They estimate that they will need $22,000 each month for two persons in today's value as living expenses for 20 years.

As regards the contributions to the MPF schemes, they are currently investing in low-risk conservative funds.

With the launching of tax deductions for the qualifying deferred annuity policy (QDAP) premiums and the tax deductible MPF voluntary contributions (TVC) as of 1 April 2019, they are considering whether they should invest in QDAP and

TVC for retirement planning.

I am confused on how to present the investment of QDAP and use what kind of reference could support my idea?