Perhaps you should try some spelling variations:
cach thoi » cac thoi, cach thuc, cach noi
hoc toan » hoc tan, hop toan, hoa toan
khoa hoc » hoa hoc
van hang » van khang, van hoang, van thang
hang tai » hang va, dung tai
anh noi » hanh noi, nang noi
cuu mon » cuu mo, cuu mot, cuu cong
mon hoc » toan hoc, dong hoc
hai van » thai van, ha van, hai tan
hoc xa » hoc ma
xa hai » xa thai, xua hai, xa hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuc ((cach thoi) or (anh noi)) dap, nghien cuu mon hoc toan khoa hoc xa hai van hang tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuc ((cach thoi) OR (anh noi)) dap, nghien cuu mon hoc toan khoa hoc xa hai van hang tai*.