Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thu sach » tu sach, thuat sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
duc van » duc va, duc manh, duc phan
tai cua » thai cua, tai cuc, tri cua

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 ((nang ma) or (nang x)) hoi. hieu vu cham ((duc van) OR (duc tan)) hanh tai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang ma) OR (nang x)) hoi. hieu vu cham ((duc van) OR (duc tan)) hanh tai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((nang ma) or (nang x)) hoi. hieu vu cham ((duc van) OR (duc tan)) hanh tai cua triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang ma) or (nang x)) hoi. hieu vu cham ((duc van) OR (duc tan)) hanh tai cua triet*.