Perhaps you should try some spelling variations:
long thuoc » luong thuoc, dong thuoc, khong thuoc
thuoc hang » thuoc khang, thuoc dang, thuoc bang
thu mach » thu sach, thuat mach, thu hoach
mach hoc » cach hoc, dich hoc, anh hoc
cuu long » cuu cong, cuu tong, cuu nang
hang hoa » hang khoa, thanh hoa, hang va
hoi danh » hop danh, hoi dan, hoi dang
hoc danh » hoc dan, hoc anh, hoc hanh
nhan tao » nhan tai, nhan dan
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: thu mach hoc tap, nghien cuu long thuoc hang hoa hoc xa ((hoi danh) or (hoc danh)) nhan tao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu mach hoc tap, nghien cuu long thuoc hang hoa hoc xa ((hoi danh) OR (hoc danh)) nhan tao.
• Adding a wildcard symbol may retrieve word variants: thu mach hoc tap, nghien cuu long thuoc hang hoa hoc xa ((hoi danh) or (hoc danh)) nhan tao*.