In November 1951, he was ambushed and killed on the way to Lien Khu III, Ninh Bình Province, before his intention of writing a novel about his country and the revolution was ever met.

Not long after that, he worked as a teacher at Công Thành, a private school in Hanoi, to earn his living while cultivating knowledge and experience to nourish his writing career.

He lived an arduous life, making both ends meet by home tutoring and writing for some newspapers until 1943 when he became a member of Hội văn hóa cứu quốc (The Cultural Association for National Salvation), a position that made him become the target of constant persecution.

However, he left the post after a few months and was dispatched to several areas around the country from 1946 to 1951, then working as an editor for Cứu quốc (National Salvation) and Văn nghệ (Literature & Arts) newspapers in Việt Bắc.

Many of his works were written during this time, notably including Đôi mắt (The Eyes) (1950), the diary Ở rừng (Living in the Forest) (1948) and the memoir Chuyện biên giới (Story in the Frontier) (1948) which won extensive praise.