Perhaps you should try some spelling variations:
sach nganh » sach ngan, sach tranh, cac nganh
nganh cong » nhanh chong, thanh cong
cach nhanh » cac nganh, cac nhan, cac thanh
khong khi » khong he
cong tac » cong ty
cong khi » cong thai, co khi, cong ha
te sach » toc sach
tu cach » tu cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach nganh cong tac đong luc ) or ( tu cach nhanh ((cong khi) or (khong khi)) đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach nganh cong tac đong luc ) OR ( tu cach nhanh ((cong khi) OR (khong khi)) đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach nganh cong tac đong luc ) or ( tu cach nhanh ((cong khi) or (khong khi)) đong luc ))*.