Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
trinh vat » trinh van, trinh luat, sinh vat
tai cao » thai cao, tai sao, tai cac
tao cao » bao cao, toan cao

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

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