Perhaps you should try some spelling variations:
sach ly » sach y, sach lo, sach ty
cua tre » cuu tre, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
va cau » van cau, va cac, va dau
cua te » cua tu

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 ly ((nang xa) or (nang ma)) hoi. hieu va cau truc va hanh vi ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ly ((nang xa) OR (nang ma)) hoi. hieu va cau truc va hanh vi ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ly ((nang xa) or (nang ma)) hoi. hieu va cau truc va hanh vi ((cua tre) or (cua te))*.