Perhaps you should try some spelling variations:
thuat mach » thuat sach, thuat tach, thuyet mach
trinh luan » trinh luat, trinh han, trinh toan
trinh quan » tinh quang, trinh luat, trinh han
nhung cong » dung cong, thong cong, hang cong
thuat tai » thuat bai, thuat tao, thuat cai
cong san » cong tac
san van » tan van, luan van, tran van

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((thuat mach) or (thuat tai)) - hanh ((trinh luan) OR (trinh quan)) nhung cong san van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((thuat mach) OR (thuat tai)) - hanh ((trinh luan) OR (trinh quan)) nhung cong san van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((thuat mach) or (thuat tai)) - hanh ((trinh luan) OR (trinh quan)) nhung cong san van ban".
• Adding a wildcard symbol may retrieve word variants: ho ((thuat mach) or (thuat tai)) - hanh ((trinh luan) OR (trinh quan)) nhung cong san van ban*.