hand to mouth

live (from) hand to mouth (to have just enough money to live on and nothing extra) — жить очень бедно, перебиваясь с хлеба на квас; едва сводить концы с концами

Example 1: My father earned very little and there were four of us kids so we lived from hand to mouth.

Example 2: Someone who's living from hand to mouth, is very poor and needs the little money they have coming in to cover their expenses.

[on the breadline ]
[scrape a living]
also scrape along
[on the breadline]
[daily bread]
[make ends meet]