Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
kinh hai » tinh hai, minh hai, dinh hai
van chat » cao chat
hieu van » hieu va, thien van, lieu va
nang ma » tang ma, sang ma, nang cao
hai cua » thai cua, dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va

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) or (thu hoach)) ky nang ma hoi. hieu van chat ((xuc va) OR (luc va)) kinh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thu hoach)) ky nang ma hoi. hieu van chat ((xuc va) OR (luc va)) kinh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thu hoach)) ky nang ma hoi. hieu van chat ((xuc va) OR (luc va)) kinh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thu hoach)) ky nang ma hoi. hieu van chat ((xuc va) OR (luc va)) kinh hai cua tre*.