Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
sach tu » sach thu, sach ty, sach uu
cach tu » cach thuc
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va chay » va chat, va cham, va cay
dua ban » dia ban, cua ban, qua ban
san cua » sang cua, ban cua, nan cua
dan cua » dan ca, ban cua, dai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach tu) or (cach tu)) nang xa hoi. hieu va chay dua ban thanh ((san cua) OR (dan cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach tu) OR (cach tu)) nang xa hoi. hieu va chay dua ban thanh ((san cua) OR (dan cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach tu) or (cach tu)) nang xa hoi. hieu va chay dua ban thanh ((san cua) OR (dan cua)) triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach tu) or (cach tu)) nang xa hoi. hieu va chay dua ban thanh ((san cua) OR (dan cua)) triet*.