Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
cong thuoc » cong thuc, long thuoc, cong thuong
dong thuoc » dung thuoc, dang thuoc, don thuoc
thanh hoa » thanh pho
sach hoi » sach doi, sach moi, cach thoi
phan van » pham van, thanh van, luan van
su sach » so sach, vu sach
hoi tap » hoi dap, hoc tap, hoi tai
va phan » van phan, va phat, va phap
hoc xa » hoc ma

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 hoi tap, nghien cua ((cong thuoc) OR (dong thuoc)) thanh hoa hoc xa hoi va phan van~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach hoi tap, nghien cua ((cong thuoc) OR (dong thuoc)) thanh hoa hoc xa hoi va phan van".
• Adding a wildcard symbol may retrieve word variants: su sach hoi tap, nghien cua ((cong thuoc) OR (dong thuoc)) thanh hoa hoc xa hoi va phan van*.