Perhaps you should try some spelling variations:
thieu quang » thien quan, trien quang, hieu quan
hieu quang » hieu quan, hieu qua, diep quang
nhanh tinh » nhanh thanh, hanh trinh, nhan sinh
nhung cong » dung cong, thong cong, hang cong
cua nhung » va nhung
tinh cua » trinh cua, sinh cua, tinh chat
cong tan » cong tac, cong san, cong thanh
gian man » gian dan, gian van, gian ban
gian lan » gian lang, gian dan, giang 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 ((hieu quang) or (thieu quang)) - nhanh tinh cua nhung cong tan ((gian man) OR (gian lan))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu quang) OR (thieu quang)) - nhanh tinh cua nhung cong tan ((gian man) OR (gian lan)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu quang) or (thieu quang)) - nhanh tinh cua nhung cong tan ((gian man) OR (gian lan))".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu quang) or (thieu quang)) - nhanh tinh cua nhung cong tan ((gian man) OR (gian lan))*.