Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
tu sach » su sach, te sach, tu cach
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cam tu » cam thu, nam tu, dam tu
vi cua » vai cua, di cua

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) or (thu sach)) ky lang xa hoi. ((hieu ve) or (hieu van)) cam tu va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky lang xa hoi. ((hieu ve) OR (hieu van)) cam tu va danh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky lang xa hoi. ((hieu ve) or (hieu van)) cam tu va danh vi cua tre*.