strike oil
Verb
Meaning
To find petroleum when boring for it.
(figuratively, informal) To have sudden good fortune, especially financially.
Source: en.wiktionary.orgExamples
My formula for success is rise early, work late, and strike oil.
I only know that all is lost, and that nothing can help me unless I inherit money, strike oil or go to work.
Rockefeller once explained the secret of success. 'Get up early, work late - and strike oil.'