Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trinh » canh tranh, hanh chinh
thong cong » trong cong, tong cong, thong thong
trinh vat » trinh van, trinh luat, sinh vat
vat thong » va thong, vat trong, mat thong
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu khang) or (chieu sang)) - hanh trinh vat thong cong ((van toan) OR (van tuan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu khang) OR (chieu sang)) - hanh trinh vat thong cong ((van toan) OR (van tuan)) tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu khang) or (chieu sang)) - hanh trinh vat thong cong ((van toan) OR (van tuan)) tap*".