Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van ban
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van bac » van ban, van bao, van hac
van anh » van thanh, tuan anh, van minh
cua tre » cuu tre, cua triet, dua tren
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: so sach ky nang xa hoi. hieu van bac xuc ((van hanh) OR (van anh)) thai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang xa hoi. hieu van bac xuc ((van hanh) OR (van anh)) thai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang xa hoi. hieu van bac xuc ((van hanh) OR (van anh)) thai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang xa hoi. hieu van bac xuc ((van hanh) OR (van anh)) thai ((cua tre) or (cua te))*.