Perhaps you should try some spelling variations:
chat long » chat luong, hai long, ha long
su sach » so sach, vu sach
ky dang » ky nang, ky danh
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » hieu qua
long va » luong va, long van, blong va
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
y dang » 2 dang, _ dang, b dang
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 ((y dang) or (ky dang)) xay hoi. ((hieu va) OR (lieu va)) chat long va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y dang) OR (ky dang)) xay hoi. ((hieu va) OR (lieu va)) chat long va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y dang) or (ky dang)) xay hoi. ((hieu va) OR (lieu va)) chat long va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((y dang) or (ky dang)) xay hoi. ((hieu va) OR (lieu va)) chat long va hanh vi cua tre*.