Perhaps you should try some spelling variations:
chiet tach » chieu sach
hoc chiet » hoc thiet, hoc nhiet, hoc hien
trinh vat » trinh van, trinh luat, sinh vat
bang cong » dang cong, bang song, hang cong
trinh ve » trinh he, trinh va, trinh vi
cong van » cong vang, cong san, song van
van phan » van phong, van thanh, luan phan
phan tap » phan lap, han tap, pha tap

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 ((trinh vat) or (trinh ve)) bang cong van phan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc chiet tach - hanh ((trinh vat) OR (trinh ve)) bang cong van phan tap.
• Adding a wildcard symbol may retrieve word variants: hoc chiet tach - hanh ((trinh vat) or (trinh ve)) bang cong van phan tap*.