Perhaps you should try some spelling variations:
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc
cua tre » cuu tre, cua triet, dua tren
y nang » ky nang, ly nang, v nang
va cam » va cham, va cac, va cao
cua te » cua tu

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

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