。
She tried to hide her feelings.
Literal
She [topic-は] her own feelings [object-を] hide [tried to-ようとした].
~ようとする ('to try to') wraps the verb 隠す ('to hide, conceal') as an attempt rather than a completed act. The past ~ようとした often carries an implication that the attempt didn't fully succeed. 感情を隠す ('to hide one's feelings') is a standard collocation, central to a culturally familiar Japanese theme: the gap between what is felt (本音) and what is shown (建前).