Perhaps you should try some spelling variations:
lieu viet » sieu viet, lieu vien, tieu viet
viet sach » viet anh, dien sach, viet tech
sach duoc » sach nuoc, sach dao, sach dung
va trinh » van trinh, va tinh, lap trinh
trinh do » trinh ky
cau treo » cau theo, cau tren, cau triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
duoc va » nuoc va, duc va, duoc ma
la tren » loai tren, dua tren, dat tren

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 ky nang xa hoi. lieu viet sach duoc va trinh do ((cau treo) or (la tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. lieu viet sach duoc va trinh do ((cau treo) OR (la tren)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. lieu viet sach duoc va trinh do ((cau treo) or (la tren))*.