Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
cau thuc » cau truc, cuu thuc, can thuc
vat hanh » vat thanh, van hanh, va hanh
te sach » toc sach
ky lang » ky dang, ky tang, tay lang
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ha hoi » hoa hoi, ha noi, xa hoi
ve cau » ke cau, va cau, ve cac
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: ((thu sach) or (te sach)) ((ky lang) or (ky nang)) ha hoi. hieu ve cau thuc vat hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (te sach)) ((ky lang) OR (ky nang)) ha hoi. hieu ve cau thuc vat hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (te sach)) ((ky lang) or (ky nang)) ha hoi. hieu ve cau thuc vat hanh vi cua tre*.