He should mind his own mine instead of interfering in her business.
Ему следует заниматься своими делами, а не вмешиваться в её дела.
Definitions
This phrase is a mistaken or altered version of the common idiom 'mind (someone's) own business,' which means to focus on one's own affairs and not interfere in others'. The use of 'mine' instead of 'business' is likely a typographical or linguistic error, and does not have a recognized meaning in English.
