Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » dung cong, thong cong, hang cong
hanh sinh » hanh dinh, hinh sinh, hanh chinh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
vat nhung » va nhung, vap nhung, vai nhung
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan tap » toan ban

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 sang) or (chieu sang)) - ((hanh sinh) OR (hanh tinh)) vat nhung cong tan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - ((hanh sinh) OR (hanh tinh)) vat nhung cong tan toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) or (chieu sang)) - ((hanh sinh) OR (hanh tinh)) vat nhung cong tan toan tap".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (chieu sang)) - ((hanh sinh) OR (hanh tinh)) vat nhung cong tan toan tap*.