Perhaps you should try some spelling variations:
nghien cua » nghien cuu, nghiep cua, nghiep vua
mach hoc » cach hoc, dich hoc, anh hoc
dan hoat » van hoa, dan hoc, danh hoa
hoat hoc » hoa hoc, hoat ho, khoa hoc
thoi dai » hoc dai, hoi dan
nhan tao » nhan tai, nhan dan
te mach » ke mach, te sach, tim mach
ban hoc » bang hoc, van hoc, bai hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: te mach hoc tap, nghien cua ban hoc dan hoat hoc ma ((hoi dap) or (thoi dai)) nhan tao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te mach hoc tap, nghien cua ban hoc dan hoat hoc ma ((hoi dap) OR (thoi dai)) nhan tao.
• Adding a wildcard symbol may retrieve word variants: te mach hoc tap, nghien cua ban hoc dan hoat hoc ma ((hoi dap) or (thoi dai)) nhan tao*.