Encryption keys are designed to look like random noise. If you simply looked for "random-looking data," you would find thousands of candidates in any given file.
Use a tool like FTK Imager or WinPmem to create a .raw or .bin dump of the target system's RAM. Run the Scan: Point AES Key Finder 1.9 at the dump file. aes key finder 19 by ghfear
Researchers use it to find the hardcoded keys malware uses to communicate with Command & Control (C2) servers. Encryption keys are designed to look like random noise