one's own eyes and ears
Refers to one's own direct observation and hearing, often used in contexts of personal experience or gathering information firsthand.
自分の目耳で確かめた情報だけを信じている。
I only trust information I've confirmed with my own eyes and ears.
Compound of 目 (め, 'eye') and 耳 (みみ, 'ear'), literally 'eyes and ears'.