Perhaps you should try some spelling variations:
thanh do » thanh de, thanh pho, thanh hoa
thanh di » thanh doi, thanh de, thanh dinh
te sach » toc sach
cua tre » cua te, cuu tre, cua triet
tang ma » mang may, tang van
hieu va » lieu va, hieu qua
sach 7 » sach y, sach 2
cam lo » nam lo, cam ly, cam o
ma hoi » mai hoi, xa hoi, ma hoa
7 tang » 6 tang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach 7 tang ma hoi. hieu va ((cam loc) or (cam lo)) va ((thanh di) or (thanh do)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach 7 tang ma hoi. hieu va ((cam loc) OR (cam lo)) va ((thanh di) OR (thanh do)) cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach 7 tang ma hoi. hieu va ((cam loc) or (cam lo)) va ((thanh di) or (thanh do)) cua tre*.