Perhaps you should try some spelling variations:
khang thuoc » khong thuoc, dang thuoc, hanh thuoc
ngan khang » ngan hang, nganh khong, van khang
long luat » cong suat, tong luan, long cua
luat ngan » cua ngan, luat dan
cuu long » cuu cong, cuu tong, cuu nang
thuoc ma » hoc ma, duoc ma
nhan tai » hang tai, van tai, toan tai
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
hoi tap » hoi dap, hoc tap, hoi tai
va nhan » van nhan, ca nhan, va phan
ma hoi » mai hoi, xa hoi, ma hoa

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) or (su sach)) hoi tap, nghien cuu long luat ngan khang thuoc ma hoi va nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) hoi tap, nghien cuu long luat ngan khang thuoc ma hoi va nhan tai.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) hoi tap, nghien cuu long luat ngan khang thuoc ma hoi va nhan tai*.