plumb (someone's) emotions

Translations
исследовать (чьи-то) эмоции
The therapist tried to plumb her emotions to understand the root of her anxiety.
Терапевт пытался исследовать её эмоции, чтобы понять причину её тревоги.
Definitions
To explore or examine someone's emotions deeply and thoroughly, often to understand their true feelings or motivations.