Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
cua tre » cuu tre, cua triet, dua tren
va cam » va cham, va cac, va cao
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

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) or (thu hoach)) ky nang x hoi. hieu va cam duc va hanh va ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thu hoach)) ky nang x hoi. hieu va cam duc va hanh va ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (thu hoach)) ky nang x hoi. hieu va cam duc va hanh va ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (thu hoach)) ky nang x hoi. hieu va cam duc va hanh va ((cua tre) OR (cua te))*.