Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
hanh trang » thanh trung, canh tranh, minh trang
hanh trinh » canh tranh, hanh chinh
hoc thien » hoc hien, hoc thieu, hoc thiet
bang cong » dang cong, bang song, hang cong
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap
va bang » va nang, va lang, va ban

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien hach - ((hanh trang) or (hanh trinh)) va bang cong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - ((hanh trang) OR (hanh trinh)) va bang cong dan toan cao*.