Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hanh dai » hanh tai, hanh dao, vanh dai
va triet » va thiet, va trien, ve triet
hoc sach » hoc sinh, hoc cac, hoc anh
nang xa » nang x, lang xa, nang ma
va hanh » van hanh, va thanh, va danh
ve cac » va cac, vien cac
dao va » dao van, tao va, do va
dai va » mai va
ve ca » ve cai, ve cau, ve 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) OR (hoc sach)) ky nang xa hoi. hieu ((ve ca) or (ve cac)) dao va hanh dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ky nang xa hoi. hieu ((ve ca) OR (ve cac)) dao va hanh dai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) ky nang xa hoi. hieu ((ve ca) or (ve cac)) dao va hanh dai va triet".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) ky nang xa hoi. hieu ((ve ca) or (ve cac)) dao va hanh dai va triet*.