Perhaps you should try some spelling variations:
doanh khoa » toan khoa
cach thoi » cac thoi, cach thuc, cach noi
hoc doanh » hoa doanh, hoc danh, hoc dan
thoi tap » toi tap, hoc tap, thoi dai
cuu cong » cua cong, thu cong, cac cong
khoa hoc » hoa hoc
nhan tai » hang tai, van tai, toan tai
va cach » va cac
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: va cach thoi tap, nghien ((cuu mo) or (cuu cong)) hoc doanh khoa hoc ma hoi va nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: va cach thoi tap, nghien ((cuu mo) OR (cuu cong)) hoc doanh khoa hoc ma hoi va nhan tai.
• Adding a wildcard symbol may retrieve word variants: va cach thoi tap, nghien ((cuu mo) or (cuu cong)) hoc doanh khoa hoc ma hoi va nhan tai*.