Perhaps you should try some spelling variations:
chieu xanh » chieu sang, chieu tinh, hieu manh
chieu sach » chinh sach, chiet tach, chieu sang
toan thuc » toan hoc, dan thuc, nhan thuc
thuc hung » thuc chung, thuc nhung, thuc dung
hung cong » nhung cong, hung cuong, phung cong
cong than » cong thanh, cong thang, cong tan
phan cac » phan dau, phan lap, phan van

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 sach)) - tinh toan thuc hung cong than ((phan cac) OR (nhan cach))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu sach)) - tinh toan thuc hung cong than ((phan cac) OR (nhan cach)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) or (chieu sach)) - tinh toan thuc hung cong than ((phan cac) OR (nhan cach))".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) or (chieu sach)) - tinh toan thuc hung cong than ((phan cac) OR (nhan cach))*.