Perhaps you should try some spelling variations:
cac luc » cau luc, coc luc, cac nuoc
lai cua » dai cua, hai cua, lai chau
sai cua » dai cua, hai cua, bai cua
va danh » va dinh, va dan, va hanh
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
luc va » duc va, tuc va, loc va
ve cac » va cac, vien cac

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

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