not know the half of it

US /nɑt noʊ ðə hæf əv ɪt/
UK /nɑt noʊ ðə hæf əv ɪt/
"not know the half of it" picture
1.

半分も知らない, 全てを知らない

to not know the full extent or all the details of a situation, especially one that is more serious or complicated than it appears

:
You think my job is tough? You don't know the half of it!
私の仕事が大変だって?あなたはその半分も知らないよ!
She's been through a lot, but her friends don't know the half of it.
彼女は多くのことを経験してきたが、友達はその半分も知らない