[Android Software Development] KaMyKaSii:
So it's confirmed that the latest devices do not make everything so easy. I decided to test the same command in a full backup I did on my old device with an MT6753 and had the following output:

matheus@matheus-CL341:/media/matheus/MULTIBOOT/fdgg$ strings -f * | grep oem
lk.img: oem p2u
lk.img: oem reboot-recovery
lk.img: oem append-cmdline
lk.img: oem off-mode-charge
lk.img: oem unlock
lk.img: oem lock
lk.img: oem key
lk.img: oem lks
lk.img: oemkeystore
lk.img: oemkeystore

I thought that nothing could be done in new devices but then I remembered what [MENTION=7718083]Spaceminer[/MENTION] said, and if it is possible to extract the bootloader? Then I analyzed the bootloader file with binwalk and had the following output:

matheus@matheus-CL341:/media/matheus/Windows10/Users/House/Downloads/Compressed/UL-ASUS_Z01KD_1-WW-15.0610.1901.22-user/firmware-update$ binwalk abl_660.elf

DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
0 0x0 ELF, 32-bit LSB executable, ARM, version 1 (SYSV)
4488 0x1188 Certificate in DER format (x509 v3), header length: 4, sequence length: 1351
5843 0x16D3 Certificate in DER format (x509 v3), header length: 4, sequence length: 1133
6980 0x1B44 Certificate in DER format (x509 v3), header length: 4, sequence length: 1149
12288 0x3000 UEFI PI Firmware Volume, volume size: 131072, header size: 0, revision: 0, EFI Firmware File System v2, GUID: 8C8CE578-8A3D-4F1C-3599-896185C32DD3
12408 0x3078 LZMA compressed data, properties: 0x5D, dictionary size: 16777216 bytes, uncompressed size: 602312 bytes

I was excited about the possible compressed data and then extracted the bootloader:

matheus@matheus-CL341:/media/matheus/Windows10/Users/House/Downloads/Compressed/UL-ASUS_Z01KD_1-WW-15.0610.1901.22-user/firmware-update$ binwalk -e abl_660.elf

DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
0 0x0 ELF, 32-bit LSB executable, ARM, version 1 (SYSV)
4488 0x1188 Certificate in DER format (x509 v3), header length: 4, sequence length: 1351
5843 0x16D3 Certificate in DER format (x509 v3), header length: 4, sequence length: 1133
6980 0x1B44 Certificate in DER format (x509 v3), header length: 4, sequence length: 1149
12288 0x3000 UEFI PI Firmware Volume, volume size: 131072, header size: 0, revision: 0, EFI Firmware File System v2, GUID: 8C8CE578-8A3D-4F1C-3599-896185C32DD3
12408 0x3078 LZMA compressed data, properties: 0x5D, dictionary size: 16777216 bytes, uncompressed size: 602312 byte

And then I ran the strings command again in the extracted abl folder and finally got what I wanted :D

matheus@matheus-CL341:/media/matheus/Windows10/Users/House/Downloads/Compressed/UL-ASUS_Z01KD_1-WW-15.0610.1901.22-user/firmware-update/_abl_660.elf.extracted$ strings -f 3078 | grep oem
3078: z[ABL] (ERROR) vb_read_oem_certificate : UNSUPPORT decrypt type = %d
3078: [ABL] vb_read_oem_certificate : OEM_CERTIFICATE type = %d, len = %d
3078: [ABL] (ERROR) vb_read_oem_certificate : ASN1X509VerifyOEMCertificate fail : %r
3078: [ABL] (ERROR) RsaVerify : vb_read_oem_certificate fail : %r
3078: [ABL] +++ cmd_oem_gen_hash()
3078: [ABL] cmd_oem_gen_hash : calculate hash_buf [%d] = %a
3078: [ABL] -- cmd_oem_gen_hash()
3078: [BL] +++ cmd_oem_update_cmdline : Cmdinfo=%s
3078: [BL] --- cmd_oem_update_cmdline : cmd_new_Info='%s'
3078: oem enable-charger-screen
3078: oem disable-charger-screen
3078: oem off-mode-charge
3078: oem select-display-panel
3078: oem device-info
3078: oem check-fuse
3078: oem gpt-info
3078: oem ssn-info
3078: oem isn-info
3078: oem adb_enable
3078: oem crc32_
3078: oem hash_
3078: oem EnterShippingMode
3078: oem rsa_test
3078: oem CPUInfo
3078: oem gen-random
3078: oem auth-hash
3078: oem reset-dev_info
3078: oem CTS_Auto
3078: oem reboot-recovery
3078: oem factory-reset
3078: oem get-batvol
3078: oem get-batcap
3078: oem update-cmdline_
3078: oem unTAR_
3078: oem show-barcode
3078: oem get_build_version
3078: oem system-info
3078: oem flash-start
3078: oem flash-end
3078: oem flash-status
3078: oem force-reset
3078: oem reset-raw
3078: oem reboot-EIO
3078: oem reset-dm_verity_count
3078: oem framdump_
3078: Enter fastboot oem off-mode-charge 0/1
3078: [ABL] cmd_oem_auth_hash - Authorized hash : PASS
3078: [ABL] (ERROR) cmd_oem_auth_hash - Authorized hash : FAILED