Perhaps you should try some spelling variations:
cong thuoc » cong thuc, dong thuoc, long thuoc
tren phan » truyen phan, trinh phan, trung phan
phan cong » thanh cong
sach hoi » sach doi, sach moi, cach thoi
cuu dong » cuu tong, cuu long, luu dong
cuu cong » cua cong, thu cong, cac cong
thuoc xa » thuoc ma, thuoc va, thuoc la
van nhan » van phan, van thanh, danh nhan
nhan van » nhan dan, nhan va, phan van
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 ((cuu dong) or (cuu cong)) tren phan cong thuoc xa hoi van nhan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoi dap, nghien ((cuu dong) OR (cuu cong)) tren phan cong thuoc xa hoi van nhan van.
• Adding a wildcard symbol may retrieve word variants: tu sach hoi dap, nghien ((cuu dong) or (cuu cong)) tren phan cong thuoc xa hoi van nhan van*.