Perhaps you should try some spelling variations:
nghien cac » nghiep cach, nghien cuu, nghiep cay
phan cung » phan cong, phan ung, phan xuong
dan thanh » dang thanh, danh thanh, ban thanh
thanh tai » thanh hai, thanh toan, doanh tai
cac cong » cua cong
cong hoc » dong hoc, cong hoa, cong coc
hoc phan » hoc dan, hoc pho
cung hoc » chung hoc, dung hoc, vung hoc
tu mach » tu cach, tu manh, tu sach
tu hach » tu hanh, tu cach, tu sach
hoi dan » hoa dan, hoc dan, hoi dap
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: ((tu mach) or (tu hach)) hoc tap, nghien cac cong hoc phan cung hoc xa hoi dan thanh tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu mach) OR (tu hach)) hoc tap, nghien cac cong hoc phan cung hoc xa hoi dan thanh tai*.