Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
dung cong » dung trong
cong thpt » cong thuc, cong thai, cong nhat
gian dan » gian lang
dan dung » van dung, tin dung, ap dung
thpt dan » thuc dan, tho dan
dan khan » dan khanh, dan chan, dan than
khan cap » khan ap, than cap, khoan cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (toc thieu)) sach - gian dan dung cong thpt dan khan cap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (toc thieu)) sach - gian dan dung cong thpt dan khan cap".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (toc thieu)) sach - gian dan dung cong thpt dan khan cap*.