Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
cong ban » cong bang, cong tan, cong dan
cong san » cong tac
thanh vi » hanh vi, thanh va, thanh ve
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
qua cua » quan cua, quang cua, qua quan
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang ma hoi. hieu qua cua ((cong ban) or (cong san)) thanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ma hoi. hieu qua cua ((cong ban) OR (cong san)) thanh vi cua triet.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ma hoi. hieu qua cua ((cong ban) or (cong san)) thanh vi cua triet*.