Perhaps you should try some spelling variations:
hieu cac » hieu luc, hieu va, hieu van
danh dai » danh dau, danh di, danh sai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cac cau » cac mau, bac cau, ca cau
truc va » thuc vat, trung va
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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. hieu cac cau ((truc va) or (thuc va)) danh dai ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu cac cau ((truc va) OR (thuc va)) danh dai ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu cac cau ((truc va) or (thuc va)) danh dai ((cua tre) or (cuu tre))*.