Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
nhung cong » thong cong, hang cong, nhung don
hanh hang » thanh hang, hang hang, hanh han
dung cong » dung trong
dan phan » doan phan, dan chan, van phan
phan cac » nhan cach, phan dau, phan lap
hang ca » hang va, nang cao, hang tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sach) OR (thien hach)) - hanh hang ca ((nhung cong) or (dung cong)) dan phan cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - hanh hang ca ((nhung cong) OR (dung cong)) dan phan cac*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (thien hach)) - hanh hang ca ((nhung cong) or (dung cong)) dan phan cac*".