Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
cao thuc » cao thuoc, can thuc, cao thu
bao thuc » cao thuoc, am thuc, va thuc
hanh vai » hanh vi, hanh va, hanh tai
va hanh » van hanh, va thanh, va danh
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang

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 ((y nang) OR (v nang)) xa hoi. lieu va ((cao thuc) or (bao thuc)) va hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((y nang) OR (v nang)) xa hoi. lieu va ((cao thuc) OR (bao thuc)) va hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((y nang) OR (v nang)) xa hoi. lieu va ((cao thuc) or (bao thuc)) va hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((y nang) OR (v nang)) xa hoi. lieu va ((cao thuc) or (bao thuc)) va hanh vai cuu tre*.