Perhaps you should try some spelling variations:
nhanh hai » nhanh thai, thanh hai, nhanh ha
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hanh hai » thanh hai, hang hai, hanh tai
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
van cam » van nam, van lam, van cau
nang ma » tang ma, sang ma, nang cao
xuc va » duc va, tuc va, luc va
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang ma hoi. hieu van cam ((xuc va) or (truc va)) ((hanh hai) or (nhanh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ma hoi. hieu van cam ((xuc va) OR (truc va)) ((hanh hai) OR (nhanh hai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ma hoi. hieu van cam ((xuc va) or (truc va)) ((hanh hai) or (nhanh hai)) cua tre*.