Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
dang xay » dang van, van xay
su sach » so sach, vu sach
tuc ban » thuc ban, truc ban, tu ban
cam tuc » cam xuc, cam tu, nam thuc
sach ly » sach y, sach lo, sach ty
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
doi su » oi su, don su, voi su
va cam » va cham, va cac, va cao
di su » ki su, da su, de su

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 ly ((nang xa) or (dang xay)) hoi. hieu va cam tuc ban thanh ((di su) OR (doi su)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ly ((nang xa) OR (dang xay)) hoi. hieu va cam tuc ban thanh ((di su) OR (doi su)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ly ((nang xa) or (dang xay)) hoi. hieu va cam tuc ban thanh ((di su) OR (doi su)) viet".
• Adding a wildcard symbol may retrieve word variants: su sach ly ((nang xa) or (dang xay)) hoi. hieu va cam tuc ban thanh ((di su) OR (doi su)) viet*.