Perhaps you should try some spelling variations:
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hien sach » dien sach, kien sach, thien hach
truong va » truong dai, truong cao, truong dao
trung va » trang va, trung ha, trung tam
dan van » dang van, doan van, dao van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien sach - hanh ((trung va) or (truong va)) ((nhung cong) or (thong cong)) dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien sach - hanh ((trung va) OR (truong va)) ((nhung cong) OR (thong cong)) dan van ban.
• Adding a wildcard symbol may retrieve word variants: hoc hien sach - hanh ((trung va) or (truong va)) ((nhung cong) or (thong cong)) dan van ban*.