Perhaps you should try some spelling variations:
kho tang » cao tang
tu sach » thu sach, su sach, tu cach
va cham » va chat, va tham
hanh di » hanh vi, hanh de, hang di
hieu va » lieu va, hieu qua
tang xa » trang xa, tang ma, lang xa
te sach » toc sach
su hien » su kien, su tien, thu hien
xuc va » tuc va, luc va, xac va
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: ((tu sach) or (te sach)) kho tang xa hoi. hieu va cham ((xuc va) OR (duc va)) hanh di su hien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) kho tang xa hoi. hieu va cham ((xuc va) OR (duc va)) hanh di su hien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) kho tang xa hoi. hieu va cham ((xuc va) OR (duc va)) hanh di su hien".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) kho tang xa hoi. hieu va cham ((xuc va) OR (duc va)) hanh di su hien*.