Wiping the sweat off his face with hands full of scars, Dat says: "My working day goes from 6a.m. until late at night around 11.30p.m. with a two-hour rest in the afternoon. I go to the market, wash dishes, keep an eye on customers' vehicles, clean tables, run around to serve customers food and beer and then anything else asked by customers. Even drinking with them is a task of mine in this restaurant."
He adds: "Working in a beer restaurant also means usually getting scolded or beaten by drunk customers for no reason. Although I feel scared, I have managed to work here and earn money for nearly two years since I left my village for Ha Noi."
"I give my mother most of the money I earn to raise my sisters and pay the hospital costs for my sick father," he says, adding that he is paid VND1.2 million (US$57) a month.
Dat is among more than 26,000 child labourers in the country who work in hard conditions with long hours and low pay and are vulnerable to physical, psychological and sexual abuse.
Nguyen Trong An, deputy head of the Ministry of Labour, Invalids and Social Affairs' Child Care and Protection Department says, "Most of child labourers have to endure long working days of over six hours a day. However, they are paid on average VND500,000 ($23) per month, equivalent to half of the minimum wage for a legal labourer working eight hours a day as regulated by the Government."
The latest report by the ministry shows that 73 per cent of child labourers are between the ages of 10 and 14, 17 per cent between the ages of 15 and 17 and 10 per cent between 6 and 9.
He says many are involved in dangerous jobs such as collecting waste in industrial parks, collecting rubber sap in rubber forests, working in mines, textile and garment factories or plastic production workshops where they come into direct contact with toxic chemicals.
He says such unhealthy and cruel working environments expose child labourers to hazardous substances, extreme temperatures, dust, noise levels or vibrations damaging to their health.
He is also concerned that most child labourers move from rural areas to cities to seek jobs and thus face risks of psychological or sexual abuse not only at work but also at their rented accommodations where they live without any protection of their families.
Dat, the employee whose family is 450km away from Ha Noi says: "I have moved four times because my rented accommodation was too dangerous for me to come back late after work. I used to be beaten and forced to give money to gangsters in the neighbourhood."
An says relevant agencies try to return child labourers to their home towns, help them resume school and get vocational training. But these efforts have little effect when they drop out of school again after several months and go back to cities to work.
He says it is also impossible for the ministry's inspectors to make regular inspections in all businesses and factories to hand out fines for employing or abusing children under 15 years old.
"We know that addressing the issue of child labour requires an understanding of its causes. The main cause for child labour in the country is poverty, which leads parents to make these decisions that put their children at risk."
Maria Luisa Rodriguez Campos, a Chief Technical Adviser of a Child Labour Project from the International Labour Organisation (ILO) Office in Viet Nam says: "Most children said they want to go to school, but many of them have no chance as they have to work to support their families."
Dat says his father used to earn the majority of the family's income but he got a serious brain injury in a traffic accident three years ago. Since then, he has undergone physical therapy for rehabilitation in a hospital.
Without his financial support, Dat's family can't afford hospital costs and their expenses as a family of five.
Rodriguez says the issue of child labour needs interventions from all levels.
"Some countries have included the issue of child labour in their cash conditional transfer programmes, set up child labour monitoring systems, or their enterprises' leaders have signed a commitment that their products are clean of children's hands."
He says a community-based system of children protection is being developed in which thousands of local volunteers and collaborators are recruited to take responsibility for detecting high risk cases of children becoming labourers or victims of violence. The group would get this kind of information, report it and support these cases' families to prevent the risks.
A national project until 2015 worth over VND1.7 trillion ($81 million) has been set up in 22 provinces and cities and will be implemented nationwide next year.
An says coupled with this, another project under review of an international partner will help child labourers' parents below the poverty line get an education and job skills training, permanent jobs and credit assistance. Rodriguez says: "ILO's child labour project, sponsored by the AECID and worth $3.2 million, aims at the prevention and progressive elimination of child labour through education, vocational training and healthcare among others."
Dat says: "I don't understand what the project means, but I hope they can help my mother get a permanent job and cover my father's hospital expenses so that I can come back home."
Just then, he is suddenly pulled back to his reality by an order for one more beer from a drunk customer.
The smile has yet to fade on his face when he loudly answers: "Yes sir, I am coming!" He runs to fetch an empty glass and disappears behind big beer barrels.