speak volumes
/ˌspiːk ˈvɒl.juːmz/idiom
to show something very clearly without words
говорить о многом, быть красноречивым
Подлежащее — поступок, взгляд или молчание, а не человек: His silence spoke volumes. Speak volumes about something.
“Her silence spoke volumes.”
“The fact that he didn’t call speaks volumes.”
“His smile spoke volumes about how he felt.”