Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
thanh lap » thanh san, phan lap, thanh hai
pham duy » pham duc
thu tang » thu trang, thu thang, thu hang
sach thu » sach thue, sach thieu, sach tham
so sach » so sanh, bo sach, co sach
cua tre » cuu tre, cua triet, dua tren
hieu vu » hieu va, hieu ve, hieu su
vu pham » su pham, vi pham, vu kham
ma hoi » mai hoi, ma hoa, me hoi
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thu tang ((ma hoi) or (xa hoi)). hieu vu pham duy vat thanh lap ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thu tang ((ma hoi) OR (xa hoi)). hieu vu pham duy vat thanh lap ((cua tre) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: so sach thu tang ((ma hoi) or (xa hoi)). hieu vu pham duy vat thanh lap ((cua tre) or (cua te))*.