Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hanh trinh » canh tranh, hanh chinh
nhung cong » thong cong, hang cong, nhung don
hoc thieu » toc thieu, hoc hien
dung cong » dung trong
manh toan » thanh toan, anh tuan, tinh toan
trinh va » trinh van, trinh vat, trinh ve
dan toan » van toan, dan than, xuan toan

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 - hanh trinh va ((nhung cong) OR (dung cong)) ((dan toan) or (manh toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - hanh trinh va ((nhung cong) OR (dung cong)) ((dan toan) OR (manh toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sach - hanh trinh va ((nhung cong) OR (dung cong)) ((dan toan) or (manh toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - hanh trinh va ((nhung cong) OR (dung cong)) ((dan toan) or (manh toan)) cao*.