Perhaps you should try some spelling variations:
thieu hach » thien hach, chieu sach, hieu cach
hanh trinh » canh tranh, hanh chinh
hoc thieu » toc thieu, hoc hien
trinh va » trinh van, trinh vat, trinh ve
song van » hoang van, trong van, duong van
cong san » cong tac
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 hach - hanh trinh va nhung ((song van) or (cong san)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu hach - hanh trinh va nhung ((song van) OR (cong san)) toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc thieu hach - hanh trinh va nhung ((song van) or (cong san)) toan cao*.