Perhaps you should try some spelling variations:
te sach » toc sach
nang xa » nang x, lang xa, nang ma
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 » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
va cam » va cham, va cac, va cao

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

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