Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
nhung cong » dung cong, thong cong, hang cong
trung va » truong va, trung ha, trung tam
trang va » tran van, hang va
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cau » 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: hoc ((thieu sach) OR (thien hach)) - hanh ((trung va) or (trang va)) nhung cong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - hanh ((trung va) OR (trang va)) nhung cong tan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (thien hach)) - hanh ((trung va) or (trang va)) nhung cong tan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) OR (thien hach)) - hanh ((trung va) or (trang va)) nhung cong tan toan cau*.