Perhaps you should try some spelling variations:
tieu sach » chieu sach, dien sach, te sach
tung cong » dung cong, tong cong, truong cong
anh tang » anh dang, anh nang, anh sang
anh bang » anh hoang, anh quang, tinh bang
duy tung » duy tuong, duc tung, duy dung
cong tan » cong tac, cong san, cong thanh
toan cau » toan ban, toan tap, toan tai
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: theo tieu sach - ((anh tang) OR (anh bang)) duy tung cong tan ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - ((anh tang) OR (anh bang)) duy tung cong tan ((toan cau) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo tieu sach - ((anh tang) OR (anh bang)) duy tung cong tan ((toan cau) or (toan cao))".
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - ((anh tang) OR (anh bang)) duy tung cong tan ((toan cau) or (toan cao))*.