After Yui's death, Takuru's family tries its best to recover. Kurusu makes a shocking admission to Takuru that she's been hiding something from him ever since he met her.  She's willing to do anything to find the killer, and she's getting very, very close...
In other words, what she was 
listening to so intently
بعبارة أخرى، ما كانت تستمع إليه بانتباه
Was sich Nono also
wiederholt angehört hat,
Por tanto debía estar mirando
la parte donde casi no se oye nada.
Por tanto debía de estar mirando
la parte donde casi no se oye nada.
Ce qui veut dire
que ce qu’elle voulait entendre,
Sendo assim, o que ela estava
 se forçando para escutar