Perhaps you should try some spelling variations:
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau tren, cau treo
va hanh » van hanh, va thanh, va danh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
lang xa » lang ha, dang xay, lang van
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 ((lang 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 ((lang 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 ((lang xa) or (nang ma)) hoi. hieu ve cham soc va hanh vi ((cuu tre) or (va thiet))*.