Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
ky lang » ky dang, ky tang, tay lang
van cam » van lam, van cau, van dam
vi cau » va cau, ve cau, di cau

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