Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
thu sach » tu sach, thuat sach, thuoc sach
cam duc » cao duc, pham duc, nam duoc
dan hai » doan hai, dang hai, dan khai
hai cua » thai cua, dai cua, hoi cua
v nang » va nang, vu nang, van nang
y nang » ky nang, ly nang, may nang
va dan » ca dan, va dao, va dau

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 ((y nang) or (v nang)) xa hoi. hieu van ((cam duc) OR (cam xuc)) va dan hai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y nang) OR (v nang)) xa hoi. hieu van ((cam duc) OR (cam xuc)) va dan hai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((y nang) or (v nang)) xa hoi. hieu van ((cam duc) OR (cam xuc)) va dan hai cua triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ((y nang) or (v nang)) xa hoi. hieu van ((cam duc) OR (cam xuc)) va dan hai cua triet*.