Dear
I have RB2011UAS used it as bridge between two networks but i have problem
i need stop discover for all RB when some one from other network open winbox must be not see my AL RB's
who can i do that

I don't know the answer but since no one has responded yet, i'll ruminate on a possible solution.
A firewall filter rule might work. here are the ports CDP uses:

CDP units use the following ports for TCP/IP communications:
22/TCP: When working with support, may be needed for SSH/console access.
443/TCP: For web UI access.
1000/TCP: Connections from local agent systems (PCs) back to the CDP device to backup files.
2022/TCP: Used for CDP unit to unit communications for offsite/box to box transfers, i.e. from CDP device communicated to another.

can i install RB2011UAS-2HnD motherboard in RB2011UAS-RM case?

You would need to drill holes for pigtails and attach antennas but it should work.

Next time you need to start your own thread.

You can turn off discovery in /ip neighbors