Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » dung cong, thong cong, hang cong
trang cua » tranh cua, tang cua, thang cua
trung cua » truong cua, trung tuan, trung cap
cong manh » cong danh, duong manh, cong thanh
manh toan » thanh toan, anh tuan, tinh toan
toan cau » 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 ((hieu nganh) or (chieu sang)) - hanh ((trang cua) OR (trung cua)) nhung cong manh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (chieu sang)) - hanh ((trang cua) OR (trung cua)) nhung cong manh toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu nganh) or (chieu sang)) - hanh ((trang cua) OR (trung cua)) nhung cong manh toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (chieu sang)) - hanh ((trang cua) OR (trung cua)) nhung cong manh toan cau*.