How I lost my bitcoin core from Mighty Hacker Recovery

I don't remember my passphrase of my bitcoin_core wallet. I try with an hex editor but I don’t know which string i have to search. how can I recover it? Thanks to all can help me. I’ve followed some post in various forums but I find only instructions for various wallet but nothing for bitcoincore. I know that is possible to find a pass phrase with an hex editor but mighty hacker recovery team of expert got them back in days. I will love to learn more about mighty hacker recovery.