Perhaps you should try some spelling variations:
kho lang » kho tang, cho lang, tho lang
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
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: ((tu sach) or (thuat song)) kho lang xa hoi. hieu van nam thu ma hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuat song)) kho lang xa hoi. hieu van nam thu ma hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuat song)) kho lang xa hoi. hieu van nam thu ma hanh vi cua tre*.