Perhaps you should try some spelling variations:
cam truong » cac truong, lam truong, cao truong
hanh trinh » canh tranh, hanh chinh
hieu tinh » chieu tinh, lieu tinh, hieu binh
kieu tinh » lieu tinh, trieu tinh, diep tinh
trinh cam » trinh cham, trinh cau, trinh tam
cong tac » cong ty
chan cau » phan cau, can cau, chinh cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu tinh) OR (kieu tinh)) - hanh trinh cam truong ((cong san) or (cong tac)) chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu tinh) OR (kieu tinh)) - hanh trinh cam truong ((cong san) OR (cong tac)) chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu tinh) OR (kieu tinh)) - hanh trinh cam truong ((cong san) or (cong tac)) chan cau".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu tinh) OR (kieu tinh)) - hanh trinh cam truong ((cong san) or (cong tac)) chan cau*.