Perhaps you should try some spelling variations:
thanh khong » thanh hong, thinh khong, thanh chuong
nghien thu » nghiem thuc, nghiep thuc, nghien cuu
hoan thanh » hoang thanh, ban thanh, van thanh
cong hoan » cong hoa, dong hoa, cong san
khong hoc » khung hoc, thong hoc, khong thuoc
phan van » pham van, thanh van, luan van
te sach » toc sach
tu sach » thu sach, su sach, tu cach
va phan » van phan, va phat, va phap
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: ((te sach) or (tu sach)) hoc tap, nghien thu cong hoan thanh khong hoc ma hoi va phan van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (tu sach)) hoc tap, nghien thu cong hoan thanh khong hoc ma hoi va phan van.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (tu sach)) hoc tap, nghien thu cong hoan thanh khong hoc ma hoi va phan van*.