Sneak off means to leave a place quietly and secretly, so that no one notices. It’s often used when someone wants to avoid attention or get away without being seen
یواشکی رفتن/دزدکی رفتن the pair sneak off to the bedroom جفتشان یواشکی ( دزدکی ) به اتاق خواب می روند
Biden sneaked off to Israel بایدن یواشکی به اسرائیل رفت