Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
xay hoi » xa hoi, cay phoi, gay thoi
tay hoi » tay ho, tao hoi, tay thai
cac duc » cac du, cao duc, cac dac
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky dang ((xay hoi) or (tay hoi)). lieu va cac duc va danh vi ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky dang ((xay hoi) OR (tay hoi)). lieu va cac duc va danh vi ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky dang ((xay hoi) or (tay hoi)). lieu va cac duc va danh vi ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky dang ((xay hoi) or (tay hoi)). lieu va cac duc va danh vi ((cua tre) OR (cua te))*.