Perhaps you should try some spelling variations:
nganh tong » nganh cong, nganh nong, nganh khong
sach nang » cach mang, sach dung, sach danh
nang cong » nang song, dang cong, bang cong
cac nganh » hoc nganh
cong khi » cong thai, khong khi, co khi
tong thi » trong thi, tang thi, dong thi
so sach » so sanh, bo sach, co sach
su cac » tu cac, su cao, su can

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sach nang cong khi đong luc ) or ( su cac nganh tong thi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sach nang cong khi đong luc ) OR ( su cac nganh tong thi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( so sach nang cong khi đong luc ) or ( su cac nganh tong thi đong luc ))*.