Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc gia » thuc giai, thue gia, thuc dia
su sach » so sach
vu sach » vu bach, vu khach
mo hoc » mon hoc, co hoc
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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) or (vu sach)) ky nang ((o hoi) or (mo hoc)). hieu van nam thuc gia thanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky nang ((o hoi) OR (mo hoc)). hieu van nam thuc gia thanh dai cua te.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu sach)) ky nang ((o hoi) or (mo hoc)). hieu van nam thuc gia thanh dai cua te*.