Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va trien » va truyen, va thiet, va tuyen
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((nang xa) or (nang ma)) hoi. hieu ve cam xuc va hanh vi ((cua tre) or (va trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((nang xa) OR (nang ma)) hoi. hieu ve cam xuc va hanh vi ((cua tre) OR (va trien)).
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((nang xa) or (nang ma)) hoi. hieu ve cam xuc va hanh vi ((cua tre) or (va trien))*.