Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh luan » trinh luat, trinh quan, trinh han
thang long » thanh cong
tieu sach » chieu sach, dien sach, te sach
hang nong » han tong
bang cong » dang cong, bang song, hang cong
dan toan » van toan, dan than, manh 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: theo tieu sach - hanh trinh luan ((((hang nong) or (bang cong))) or (thang long)) dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo tieu sach - hanh trinh luan ((((hang nong) OR (bang cong))) OR (thang long)) dan toan cau.
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - hanh trinh luan ((((hang nong) or (bang cong))) or (thang long)) dan toan cau*.