Perhaps you should try some spelling variations:
ban hanh » ban hang
hieu van » hieu va, thien van, lieu va
van chat » cao chat
chat xuc » chat huu, cam xuc, chao xu
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
ca tren » cau tren, cu tren, la tren
va hanh » van hanh, va thanh, va danh
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa

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 ky nang ma hoi. hieu van chat xuc ((va hanh) or (ban hanh)) dai ((cua tre) or (ca tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ma hoi. hieu van chat xuc ((va hanh) OR (ban hanh)) dai ((cua tre) OR (ca tren)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ma hoi. hieu van chat xuc ((va hanh) or (ban hanh)) dai ((cua tre) or (ca tren))*.