Perhaps you should try some spelling variations:
kho tang » cao tang
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
tang xa » trang xa, tang ma, lang xa
ma hanh » va hanh, da hanh, na hanh
cua tre » cua te, cuu tre, cua triet
thu ma » thuc ma, thu ha, tu ma
vi cua » vai cua, di cua

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) or (thuat song)) kho tang xa hoi. hieu van nam thu ma hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thuat song)) kho tang xa hoi. hieu van nam thu ma hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thuat song)) kho tang xa hoi. hieu van nam thu ma hanh vi cua tre*.