Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thu sach » tu sach, thuat sach, thuoc sach
cam thuc » am thuc, nam thuc, cam thu
vat lanh » dat lanh, hat lanh, va lanh
sach ky » sac ky, sach y, sach ty
hieu va » hieu qua
dao cua » dai cua, day cua, dan cua
nang o » nang co, nang ho, nang ro
o hai » co hai, so hai, o lai

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang o hai. ((hieu va) OR (lieu va)) cam thuc vat lanh dao cua triet~.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang o hai. ((hieu va) or (lieu va)) cam thuc vat lanh dao cua triet*.