Perhaps you should try some spelling variations:
nhung cong » thong cong, hang cong, nhung don
hien manh » hien hanh, tien manh, hieu manh
trinh van » trinh han, trinh quan, trinh toan
dung cong » dung trong
trinh va » trinh vat, trinh ve, trinh vi
sat phan » sat nhan, vat phan, xuat phan
phan dau » phan tu, hang dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien manh - canh ((trinh va) OR (trinh van)) ((nhung cong) or (dung cong)) sat phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien manh - canh ((trinh va) OR (trinh van)) ((nhung cong) OR (dung cong)) sat phan dau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien manh - canh ((trinh va) OR (trinh van)) ((nhung cong) or (dung cong)) sat phan dau".
• Adding a wildcard symbol may retrieve word variants: hoc hien manh - canh ((trinh va) OR (trinh van)) ((nhung cong) or (dung cong)) sat phan dau*.