Perhaps you should try some spelling variations:
dang xay » dang van, van xay
co sach » bo sach, cuon sach, hoc sach
hang di » hang doi, hang vi, hang dien
va hang » van hang, va nang, va lang
cam tuc » cam xuc, cam tu, nam thuc
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
lang xa » lang ha, lang van
su viet » so viet
tuc va » thuc va, truc va, tuc xa
di su » doi su, ki su, da su

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ty ((lang xa) or (dang xay)) hoi. ((hieu ve) or (hieu qua)) cam tuc va hang di su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ty ((lang xa) OR (dang xay)) hoi. ((hieu ve) OR (hieu qua)) cam tuc va hang di su viet.
• Adding a wildcard symbol may retrieve word variants: co sach ty ((lang xa) or (dang xay)) hoi. ((hieu ve) or (hieu qua)) cam tuc va hang di su viet*.