How to configure ip tcp adjust-mss on Mikrotik

Please I have an issue with my site. Its running with mikrotik router os (RB-3011). The ISP now complain that they want to work on a cisco device to be able to set a command - “ip tcp adjust-mss 1432” before I can browse all site. On mikrotik router it’s only browsing google, youtube, facebook only. But on the cisco router it’s browsing all sites I have been battling to get the link on mikrotik router but can’t really figure out how to configure that particular aspect to get it working. Please assist me and advice me as well. Were can I set the command “ip tcp adjust-mss 1432”

You can do the same:
https://wiki.mikrotik.com/wiki/Manual:IP/Firewall/Mangle#Change_MSS

Clamp TCP MSS

Do Change automaticly MSS over MTU tunnel???

I don’t seems to understand your question? are you asking if the value changes automatically ? no it does not. Please i just need a procedure on how to make that work.

Did you see the link I posted?

yes

My question is if my tunnel mtu 1480 and enable Clamp tcp mss

whether automatly Change packet TCP mss to 1440???

see this link pls
http://blog.ipspace.net/2013/01/tcp-mss-clamping-what-is-it-and-why-do.html

Yes Normis I saw the Link You sent but i needed a more practical approach to succeed.