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 cua » tinh cua, trinh luat, trinh quan
cua thong » cua thuong, cua khong, cua tong
toan cao » toan ban, toan tap
tan can » toan can, tan van, ban can

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 cua thong thong ((tan can) or (toan cao)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu hach - hanh trinh cua thong thong ((tan can) OR (toan cao)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu hach - hanh trinh cua thong thong ((tan can) or (toan cao)) cau*.