Perhaps you should try some spelling variations:
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
thu sach » tu sach, thuat sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
toan hoa » toan khoa, toan hoat, toan hoc
thai van » thi van, thanh van, thai vung
cong so » cong san, cong hoa
so toan » so tan, so than, bao toan
hai van » ha van, hai tan, hao van
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 sach hoc tap, nghien thu cong so toan hoa hoc xa ((hai van) or (thai van)) thanh san~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach hoc tap, nghien thu cong so toan hoa hoc xa ((hai van) OR (thai van)) thanh san.
• Adding a wildcard symbol may retrieve word variants: thu sach hoc tap, nghien thu cong so toan hoa hoc xa ((hai van) or (thai van)) thanh san*.