Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
trung tuan » trung thanh, trung tam, tran tuan
cong ngang » cong nhan, cong quang, cong lang
hoc thieu » toc thieu, hoc hien
trung cap » truong cao, trung tam
cong vang » cong lang, cong quang, cong san
than cau » toan cau, phan cau, than cap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - thanh ((trung tuan) OR (trung cap)) trong ((cong vang) OR (cong ngang)) than cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - thanh ((trung tuan) or (trung cap)) trong ((cong vang) OR (cong ngang)) than cau~".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - thanh ((trung tuan) or (trung cap)) trong ((cong vang) OR (cong ngang)) than cau*.