Perhaps you should try some spelling variations:
thuong cong » thong cong, thuong con, thuong dong
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
trung cao » truong cao, trung cap, trung ca
trung co » trung bo, trong co, truong cao
cong tac » cong ty
nhan tap » nhan tao, han tap, phan tap
nhan tai » hang tai, van tai, toan tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo chieu sach - hanh ((trung cao) or (trung co)) thuong cong tac ((nhan tap) OR (nhan tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - hanh ((trung cao) OR (trung co)) thuong cong tac ((nhan tap) OR (nhan tai)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chieu sach - hanh ((trung cao) or (trung co)) thuong cong tac ((nhan tap) OR (nhan tai))".
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - hanh ((trung cao) or (trung co)) thuong cong tac ((nhan tap) OR (nhan tai))*.