Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
van thuong » va thuong, van chuong, van phuong
phuong van » phong van, phuong lan, phuong va
doi chieu » doc hieu, doi chi, mot chieu
canh luan » doanh luan, tranh luan, chinh luan
ban tap » bai tap, han tap, ban tai

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu tinh - canh luan van thuong ((phuong van) OR (phung van)) ban tap~.
• Adding a wildcard symbol may retrieve word variants: doi chieu tinh - canh luan van thuong ((phuong van) or (phung van)) ban tap*.