Perhaps you should try some spelling variations:
chiet tach » chieu sach
hoc chiet » hoc thiet, hoc nhiet, hoc hien
hanh manh » hanh mang, hoang manh, thanh minh
lanh manh » lanh tranh, lan anh, van manh
dung cong » dung trong
qua dung » quang dung, su dung, qua song
ban chat » bao chat, luan chat, cao chat
van chat » cao chat

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc chiet tach - ((hanh manh) OR (lanh manh)) qua dung cong ((ban chat) or (van chat)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - ((hanh manh) OR (lanh manh)) qua dung cong ((ban chat) OR (van chat)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc chiet tach - ((hanh manh) OR (lanh manh)) qua dung cong ((ban chat) or (van chat)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc chiet tach - ((hanh manh) OR (lanh manh)) qua dung cong ((ban chat) or (van chat)) cao*.