Perhaps you should try some spelling variations:
chet duoc » che duoc, cho duoc, che quoc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
ve chet » ve chat, ve che, se chet
duoc va » nuoc va, duc va, duoc ma
va hanh » van hanh, va thanh, va danh
vai cua » hai cua, lai cua, bai 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 ky ((nang xa) OR (nang x)) hoi. hieu ve chet duoc va hanh ((vai cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang x)) hoi. hieu ve chet duoc va hanh ((vai cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (nang x)) hoi. hieu ve chet duoc va hanh ((vai cua) or (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (nang x)) hoi. hieu ve chet duoc va hanh ((vai cua) or (dai cua)) tre*.