Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu tinh, hieu manh
chieu sang » chieu sach, hieu lang, nhieu tang
nho phuong » pho phuong, nhu phuong, nho thuong
phuong dan » phuong danh, phuong doan, huong dan
trinh va » trinh van, trinh vat, trinh vi
trinh ve » trinh he, trinh vi, trinh viet
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu xanh) OR (chieu sang)) - hanh ((trinh va) or (trinh ve)) nho phuong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sang)) - hanh ((trinh va) OR (trinh ve)) nho phuong dan toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) OR (chieu sang)) - hanh ((trinh va) or (trinh ve)) nho phuong dan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) OR (chieu sang)) - hanh ((trinh va) or (trinh ve)) nho phuong dan toan cao*.