Searching & fetching email too slow

[Ellen]

Hi Tanya,
Have a nice day.
I have issue about fetching & searching email.It's taken to long time.
Could you help to investigate the reason.
As I check the CPU of sql server is to high.Once I search in email, CPU will increase.
Please check and advise the solution since it's affected to our user working once they use email.
Thank you very much.