Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
hoa thanh » hoan thanh, ha thanh, hoc thanh
thanh hoa » thanh pho
sach hoi » sach doi, sach moi, cach thoi
cong hoa » dong hoa, dong hoc, hang hoa
van phan » van phong, van thanh, luan phan
phan dan » phan dang, phan dau, nhan dan
tu sach » thu sach, su sach, te sach
hoi van » hoi va, hoi dan, hai van

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach hoi dap, nghien cua cong hoa thanh hoa ((hoc xa) or (hoc ma)) hoi van phan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoi dap, nghien cua cong hoa thanh hoa ((hoc xa) OR (hoc ma)) hoi van phan dan.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi dap, nghien cua cong hoa thanh hoa ((hoc xa) or (hoc ma)) hoi van phan dan*.