旧事难寸旧梦难忘
[jiù shì nán cùn jiù mèng nán wàng]
Translates to 'Old memories are hard to measure; once dreamed, not easy to forget'. The person is likely nostalgic about their past experiences. Old dreams and stories have made a deep impression that can’t be easily erased, symbolizing the strong effect of old recollections on current life and choices.