Perhaps you should try some spelling variations:
luan hang » luan nang, luan han, luan hung
cham dung » chan dung, pham dung, chao mung
cau tren » cu tren, dau tren, ca tren
hang hoi » hang hoa, hang hai, hang doi
cuu tre » cua tre, cau treo
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
dai hoi » dai hoc, dai hai, dai moi
mai hoi » mai khoi, lai hoi, mai doi
ve cham » va cham, ve chat, vu cham

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 ((mai hoi) or (dai hoi)). hieu ve cham dung luan hang hoi ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((mai hoi) OR (dai hoi)). hieu ve cham dung luan hang hoi ((cuu tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((mai hoi) or (dai hoi)). hieu ve cham dung luan hang hoi ((cuu tre) or (cau tren))*.