Hello Liangtao,
See below advice, please!
--Contacting local distributor of NXP(FAE or Sales)
--Distributor helps you sign NDA with NXP
--Registering an account on "http://www.docstore.nxp.com/ "
--Applying for authority on product you want to use
--Applying corresponding documents you want.
--waiting for approval.
Have a nice day!
TIC weidong sun