Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
va hanh » van hanh, va danh, ban hanh
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
vi cua » vai cua, di cua
ve cam » ve cham, ve cac, va cam

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

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