Perhaps you should try some spelling variations:
dia thanh » gia thanh, da thanh, dinh thanh
thanh dat » thanh san, thanh hai, thanh van
thuoc dia » thuc dia, thuoc dieu, thuoc giao
nam thuoc » nam thuc, nam thu, nha thuoc
hieu van » hieu va, thien van, lieu va
su sach » so sach
dat cua » dai cua, day cua, mat cua
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 thuoc dia thanh dat 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 thuoc dia thanh dat 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 thuoc dia thanh dat cua te*.