冷言冷语却知心甜言蜜语不知心
[lĕng yán lĕng yŭ què zhī xīn tián yán mì yŭ bù zhī xīn]
'Cold words but heartfelt; sweet words may not come from the heart' suggests that this person might value sincerity in relationships. They prefer blunt, honest people to overly flattering ones, emphasizing the essence of truth over superficial politeness.