This picture taken on March 1, 2016 shows a man running a mobile pig mating service and waiting outside a customer's home with his male pig in a cage pulled behind his motorcycle in the northern province of Bac Ninh. (Photo by Hoang Dinh Nam/AFP Photo)

A little girl stands next to a painted buffalo during the “Buffalo Painting” contest that is part of the Tich Dien festival in Ha Nam province, Vietnam, 10 February 2019. Artists from all over the country have gathered for the festival which attracts thousand of residents and visitors. Tich Dien festival features the importance of agriculture and the role of farmers in the vietnamese society and contributes to preserving the local cultural values. (Photo by Luong Thai Linh/EPA/EFE)

Pupils of the Dao ethnic tribe return home from school along a hillside path at Suoi Thau village in Hoang Su Phi district of Vietnam's northern province of Ha Giang, located at the border with China, September 18, 2015. (Photo by Reuters/Kham)

Thousands of bright yellow silkworm cocoons are dried in huge clay bowls in the village of Hong Ly, northern Vietnam in July 2022. Silk fibres are produced by silkworms when they spin themselves into a cocoon on their journey to becoming a silkmoth. The ultra-soft fibres are harvested from the cocoon in their raw state by being boiled in hot water. (Photo by Prabu Mohan/Solent News)