2007 - 2008: Participating in the United Nations Program, UNDP on environmental treatment and protection in Quang Ninh mine area. Practical research, data collection, making rules for environmental and rehabilitation protection in the process of mining, waste rock discharge, surface wastewater, dust treatment, exhaust gases from surface and underground mines in Quang Ninh area.

2014: Responding to a doctoral thesis on "Research on overall management and technical solutions for environmental rehabilitation and restoration work for open-cast mines in Hon Gai-Cam Pha area".

2016: Participating in the project Researching solutions for environmental restoration of mining quarry in Dong Nai province.Applying methods of burying waste in Australia's open-pit mines in Dong Nai mines to bury waste in Ho Chi Minh City, Dong Nai province. Recovery of methane (CH4) for electricity generation.

2015 - 2017: Successful research of sludge treatment technology for acid wastewater pH = 2.5 - 3 at Na Duong coal mine.

From 2016: Research and develop technologies for treatment of bio - chemical sludge and industrial sludge, industrial waste and hazardous waste of domestic steel complexes instead of burning and burial methods, which are does not solve the environmental impacts.

SIERRA's scientific staffs guides and reviews many master's theses on the environment field.