Perhaps you should try some spelling variations:
trinh thuat » trinh luat, trinh thiet, trinh chat
nhung huong » nhung phuong, nhung tuong, nhung cong
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
trinh thuc » trinh tu, trinh thi
dan than » dan chan, ban than, van than
than tap » toan tap, han tap, phan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo chieu sach - hanh ((trinh thuat) or (trinh thuc)) nhung huong dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo chieu sach - hanh ((trinh thuat) OR (trinh thuc)) nhung huong dan than tap.
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - hanh ((trinh thuat) or (trinh thuc)) nhung huong dan than tap*.