Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
ve cham » va cham, ve chat, vu cham
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
vi cua » vai cua, di cua

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 hoa. hieu ((ve cham) or (va cao)) ((thuc vat) or (thuc dan)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ma hoa. hieu ((ve cham) OR (va cao)) ((thuc vat) OR (thuc dan)) hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ma hoa. hieu ((ve cham) or (va cao)) ((thuc vat) or (thuc dan)) hanh vi cua tre*.