16.04 - USB not shown in UEFI boot option

I'm new user. I'm using Asus x550j with Windows 10. I've created bootable USB with Ubuntu 16.04 using Rufus.
In uefi I've already set Fast Boot - disabled,Launch CSM - enabled, Secure Boot- disabled but my USB isn't shown in the boot option list. And the list doesn't show my usb port in general while it shows CD drive event though no CD is placed.
I will be very grateful to anybody who could provide advices or insights!