Salary

Perhaps you should clarify your question, more clearly.

The minimum wage for a Thai is 300 baht a day. It does not seem to be unusual that a Thai has to work six days a week.

Sorry for the confusion, but I just would like to check as I received a proposal from one organization agreed to pay me about 2000bath/day and some Thai people said that is very low.
That's make very curious about the minimum wage for Thai people.

A quick Google will give you the following numbers.  A more extensive search on your own may come up with something more up to date.  Good searching...

*. European countries (except Russia), Australia continent, Canada, Japan, and U.S.A.
Baht 50,000/month

*. South Korea, Singapore, Taiwan and Hong Kong.  Baht 45,000/month

*. Asian countries (except Japan, South Korea, Singapore, Taiwan, Hong Kong, Cambodia, Myanmar, Laos and Vietnam), South America continent, Countries in Eastern Europe, Countries in Central America, Mexico, Turkey, Russia and South Africa
Baht 35,000/month

*. African countries (except South Africa), Cambodia, Myanmar, Laos and Vietnam
Baht 25,000/month