Perhaps you should try some spelling variations:
thanh thai » thanh hai, thanh tai, nhanh thai
thai cua » than cua, tai cuc, tri cua
truc va » thuc vat, trung va
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
sach ky » sach y, sach ty, sach kem
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
va cau » van cau, va cac, va dau

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