Perhaps you should try some spelling variations:
co thua » o thua, cho thue
lai cua » dai cua, hai cua, lai chau
vai cua » dai cua, hai cua, bai cua
va hanh » van hanh, va thanh, va danh
thua va » thuat va, chua va, thuat vat
sach tu » sach thu, cach tu, sach uu
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach thu, xach tay
va co » vo co

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach tu) OR (sach ty)) nang xa hoi. hieu va co thua va hanh ((vai cua) or (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach tu) OR (sach ty)) nang xa hoi. hieu va co thua va hanh ((vai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach tu) OR (sach ty)) nang xa hoi. hieu va co thua va hanh ((vai cua) or (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach tu) OR (sach ty)) nang xa hoi. hieu va co thua va hanh ((vai cua) or (lai cua)) tre*.