Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
hanh trinh » canh tranh, hanh chinh
cac phuong » cac truong
hien sach » dien sach, kien sach, thien hach
trinh cac » trinh cau, trinh chat, trinh chao
cong san » cong tac
gian cac » gian dan
gian cua » gian xu, ban cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien sach - hanh trinh cac phuong cong san ((gian cac) or (gian cua))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien sach - hanh trinh cac phuong cong san ((gian cac) OR (gian cua)).
• Adding a wildcard symbol may retrieve word variants: hoc hien sach - hanh trinh cac phuong cong san ((gian cac) or (gian cua))*.