at cross purposes

Translations
говорить о разных вещах
We were talking at cross purposes during the meeting.
На встрече мы говорили о разных вещах.
Definitions
In a situation where two or more people have conflicting goals or intentions, leading to misunderstandings or ineffective communication.
Words
at

preposition
в
cross

adjective
противоположные
purposes

noun
цели