The SMBIOS OEM strings are not displayed in BIOS Setup (or within Intel(R) Visual BIOS). They are carried in the SMBIOS structure table (Type 11 structure(s)) and can be displayed in runtime environments such as Windows, Linux, etc. Various 3rd-party applications are available that can display this information. In the Windows environment, you can use tools like AIDA64 or RWEverything (Read-Write Everything) to display this information. Similarly, in the Linux environment, you can use tools like Dmidecode to display this information.
P.S. I have filed an enhancement request for the inclusion of the OEM Strings in the information display scene of Intel(R) Visual BIOS