Qian, together with another 70 returned scientists and scholars, issued a written proposal in 1955, in which they talked about their work and life in China and motivated other Chinese expatriates in the United States to move back and join the construction of New China. A copy of this proposal is on show at the current exhibition.

Chen says the exhibition mostly introduces the deeds of unsung heroes of the returned overseas Chinese, such as Zheng Jia, who returned from Singapore and participated in scientific surveys in the Tibet autonomous region and Qinghai province for railway construction in the 1970s. A toolbox which Zheng carried with him during the surveys is a highlight of the exhibition.

Retired teacher, Qiu Yiming, 83, vividly recollects how he prepared for a journey to China 62 years ago, setting out from Indonesia, where he was born and raised.

Qiu, alongside dozens of students of Chinese origin, whom he taught at a middle school, boarded a steamer in Bandung in 1957. They were among many groups of young people who headed for the land of their ancestry with the hope and desire to build a new China.

The exhibition has a handwritten list made by Qiu of objects he thought would be needed in China, such as medicines, clothes and stationary.

"I also listed sweaters and woolen threads, because many students didn't realize that they needed something to keep them warm in a country which, unlike Indonesia, is not hot all the year around," Qiu says.

Between 1949 and 1968, more than 70,000 overseas Chinese in their teens and early 20s arrived on the mainland and continued to study, work and live, according to figures from the All-China Federation of Returned Overseas Chinese.

Qiu donated the list, together with the suitcase he carried, to the Overseas Chinese History Museum of China when it was founded.

"I want to leave something for the future generations. I hope they will learn of our experiences," he says.