Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
soc va » hoc va, loc va, doc va
thiet » thieu

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 xa) or (nang ma)) hoi. hieu ve cham soc va hanh vi ((cuu tre) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang ma)) hoi. hieu ve cham soc va hanh vi ((cuu tre) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (nang ma)) hoi. hieu ve cham soc va hanh vi ((cuu tre) or (va thiet))*.