Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hoc thieu » toc thieu, hoc hien
trinh vat » trinh van, trinh luat, sinh vat
trinh va » trinh van, trinh ve, trinh vi
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
phan cau » phan dau, phan cac, phan tu

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 - canh ((trinh va) OR (trinh vat)) nhung ((cong dan) or (cong san)) phan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - canh ((trinh va) OR (trinh vat)) nhung ((cong dan) OR (cong san)) phan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - canh ((trinh va) OR (trinh vat)) nhung ((cong dan) or (cong san)) phan cau".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - canh ((trinh va) OR (trinh vat)) nhung ((cong dan) or (cong san)) phan cau*.