Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dang hai » dang khai, hang hai, dung hai
danh hai » lanh hai, manh hai, danh hau
thu sach » tu sach, thuat sach, thuoc sach
che duoc » che thuoc, che do, te duoc
hieu de » hieu ve, hieu he, hieu le
duoc va » nuoc va, duc va, duoc ma
ky sang » ky dang, ky tang, duy sang
de che » ke che

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ky sang) or (ky nang)) xa hoi. hieu de che duoc va ((danh hai) OR (dang hai)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky sang) OR (ky nang)) xa hoi. hieu de che duoc va ((danh hai) OR (dang hai)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ky sang) or (ky nang)) xa hoi. hieu de che duoc va ((danh hai) OR (dang hai)) cua triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky sang) or (ky nang)) xa hoi. hieu de che duoc va ((danh hai) OR (dang hai)) cua triet*.