Sending Money To Us From Bkk

I am a bit embarrassed to expose my ignorance.

But, I only have a savings account at K Bank in BKK and would like to withdraw a fairly large sum of money and send it to my son in the US. Is there such a thing as Cashier's check or some other instrument available that I could use?

I have been to K Bank on Silom for other matters and have found English language skills to be lacking, making inquiries at K Bank difficult.

Thanks for help in this matter.