Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
nang huong » nang thuong, nang luong, hang thuong
hien sach » dien sach, kien sach, chieu sach
nang hang » nang sang, hang hang, cang thang
dan chan » dan gian, dan ca, van chat
chan cau » phan cau, can cau, chinh cau
va nang » van nang, da nang, cam nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien sach) or (thien hach)) - nang hang va nang huong dan chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sach) OR (thien hach)) - nang hang va nang huong dan chan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) or (thien hach)) - nang hang va nang huong dan chan cau*.