Edit your virtual machine -> usb -> Click on the little USB logo with the Green plus signal. Add the usb device you want to show to your guest OS. Be happy. :)
If you see them in the list, but they fail in installing driver, check to see you have USB2.0 enabled in virtualbox settings. USB1.0 is set by default and will not be able to install USB 2.0 drivers. The program may prompt you to install an extension pack for this. Once USB 2.0 (or 3.0 if you have a USB3.0) is enabled, the USB should attach and proper drivers installed.
If that does not work, you will probably need to disable that device inside host and enable it in guest. There is an awesome and complete tutorial at Ask Ubuntu, related to this question:
I know that i should not link external how-tos here, but this is a matter of not repeating something that other people have already answered inside SE sites.
Another detail is that, for Windows guests the following limitations apply:
- Windows 7 needs an additional driver for USB 3.0 support.
- Windows 10 does not accept an NTFS formatted USB pen drive.