Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
trinh quan » tinh quang, trinh luat, trinh han
khong cang » thong cong, hong bang, khong dung
trinh cua » tinh cua, trinh luat, trinh luan
cang cao » nang cao, cong cao, lang cao
chat van » chat va, chat ban, chat ran

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 sang) or (chieu sach)) - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu sach)) - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (chieu sach)) - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu sach)) - hanh ((trinh cua) OR (trinh quan)) khong cang cao chat van*.