Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
danh noi » hanh noi, anh noi, dang noi
trung va » truong va, trang va, trung ha
va triet » va thiet, va trien, ve triet
van hac » van hoc, van ha, van hai
ky dang » ky nang, ky danh
va danh » va dinh, va dan, va hanh
ky lang » ky nang, ky tang, tay lang
van cac » van cau, van bac, dan cac
noi va » hoi va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ((ky lang) OR (ky dang)) xa hoi. hieu ((van cac) or (van hac)) trung va danh noi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ((ky lang) OR (ky dang)) xa hoi. hieu ((van cac) OR (van hac)) trung va danh noi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ((ky lang) OR (ky dang)) xa hoi. hieu ((van cac) or (van hac)) trung va danh noi va triet".
• Adding a wildcard symbol may retrieve word variants: hoc sach ((ky lang) OR (ky dang)) xa hoi. hieu ((van cac) or (van hac)) trung va danh noi va triet*.