@mingjie0409
there has been some discussion of this here: https://buddypress.org/support/topic/bussdypress-title-and-seo-yoast-problem/#post-253510
and here:
https://premium.wpmudev.org/forums/topic/bp-meta-tite-description-for-groups-and-members-pages
and several other places including the suggestions / feedback area amongst others.
I’ve had it fixed a time or two but updates to either bp or themes have broken my fixes.
This is something that google’s webmaster tools screams at you as being bad, and hurts your site the more members you get.
so I added a noindex no follow to the robots.txt file to remove most of the bp pages from being indexed.
