Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
cay qua » cau qua, cac qua, cay lua
vai cua » dai cua, hai cua, lai cua
bay qua » ban quan, bao quan, bach qua
sach ky » sac ky, sach ty, sach kem
sang ma » tang ma, nang ma, sang tao
cua tre » cua te, cuu tre, cua triet

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