Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
ty lang » tay lang, ty hang, tu lang
hieu ve » hieu va, hieu van
cam cua » ca cua, nam cua, cau cua
danh vi » hanh vi, danh di, danh va
dinh vi » dinh ve, dinh viet, dinh tri
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam

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 ((ty lang) OR (ty xang)) xa hoi. hieu ve cam cua ban ((danh vi) or (dinh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ve cam cua ban ((danh vi) OR (dinh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ve cam cua ban ((danh vi) or (dinh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty lang) OR (ty xang)) xa hoi. hieu ve cam cua ban ((danh vi) or (dinh vi)) cua tre*.