Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
thuc va » thuc vat, thuc dan, thuc day
tinh va » tich va, trinh van, trinh vat
cua tre » cua te, cuu tre, cua triet
tuc va » truc va, tuc xa, duc va
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang xa hoi. ((hieu va) or (lieu va)) lam ((tuc va) or (thuc va)) tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu va) OR (lieu va)) lam ((tuc va) OR (thuc va)) tinh va cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu va) or (lieu va)) lam ((tuc va) or (thuc va)) tinh va cua tre*.