Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vai » thanh hai, thanh van, thanh tai
hieu van » hieu va, thien van, lieu va
vay luan » ly luan, von luan, bai luan
tu sach » thu sach, su sach, te sach
cac qua » cau qua, tac quan
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
sach ty » sach y, sach tu, sach thu
cay qua » cau qua, cay lua, cay dua
sang ma » tang ma, nang ma, sang tao
ty sang » ty xang, ty hang, duy sang

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 ty sang ma hoa. hieu van ((((cay qua) OR (cac qua))) or (vay luan)) ban thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty sang ma hoa. hieu van ((((cay qua) OR (cac qua))) OR (vay luan)) ban thanh vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty sang ma hoa. hieu van ((((cay qua) OR (cac qua))) or (vay luan)) ban thanh vai cua tre*".