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