Member Server cannot search AD user (another domain) but DC can

Dear Support, 

We have the Forest Trust between 2 domains on production environment. 
DC (Domain-A) can find the user account on DC (Domain-B) and vice versa. 
However, Member Server (Domain-A) cannot find the user (Domain-B) but Member Server (Domain-B) can find the user (Domain-A). 
Could you have idea for our situation?
Besides, could it have any impact when we click "Validate" button when there is the existing Forest Trust?


Reference:
Verify a trust
https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2003/cc737447(v=ws.10)

Thanks!

Best Regards, 

Daniel