Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
hanh de » hanh ve, hanh kem
cac thu » cach thuc, cac thoi
su sach » so sach, vu sach
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
cam thu » nam thu, ca thu, cam phu
de su » den su, ve su, de tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y ((nang xa) OR (nang x)) hoi. hieu ve ((cam thu) or (cac thu)) van hanh de su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y ((nang xa) OR (nang x)) hoi. hieu ve ((cam thu) OR (cac thu)) van hanh de su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y ((nang xa) OR (nang x)) hoi. hieu ve ((cam thu) or (cac thu)) van hanh de su triet*".