Perhaps you should try some spelling variations:
tan thanh » tran thanh, tang thanh, toan thanh
thanh tai » thanh hai, thanh toan, doanh tai
su sach » so sach, vu sach
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
sach ty » sach y, sach tu, sach thu
va chat » van chat, va phat, hoa chat
may hoa » may khoa, ma hoa, day hoa
ty mang » ty xang, ty hang, tin mang

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 ty mang may hoa. hieu ((va chat) or (cao chat)) duc tan thanh tai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty mang may hoa. hieu ((va chat) OR (cao chat)) duc tan thanh tai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty mang may hoa. hieu ((va chat) or (cao chat)) duc tan thanh tai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach ty mang may hoa. hieu ((va chat) or (cao chat)) duc tan thanh tai ((cua tre) OR (cuu tre))*.