Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
pham thuc » phap thuc, pham chuc, nham thuc
thanh doi » thanh loi, thanh moi, thanh do
hieu van » hieu va, thien van, lieu va
van pham » san pham, van phan, van phat
sach ky » sac ky, sach ty, sach kem
doi cua » dai cua, hoi cua
co hoi » co hoc, co loi
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: thu ((sach ky) or (sach y)) nang ((cau hoi) or (co hoi)). hieu van pham thuc vat thanh doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sach y)) nang ((cau hoi) OR (co hoi)). hieu van pham thuc vat thanh doi cua te.
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sach y)) nang ((cau hoi) or (co hoi)). hieu van pham thuc vat thanh doi cua te*.