Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » dung cong, thong cong, hang cong
trinh toan » tinh toan, thanh toan, trinh han
trang va » tran van, hang va
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 trang va nhung cong trinh toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - hanh trang va nhung cong trinh toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - hanh trang va nhung cong trinh toan cau*.