Perhaps you should try some spelling variations:
nang cau » nang cao, hang cau, nang dau
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
va cao » va cac, va co, va bao
va dao » ca dao
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: tu sach ky nang cau hoi. lieu ((va cao) OR (va dao)) suc ((va hanh) or (va danh)) vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang cau hoi. lieu ((va cao) OR (va dao)) suc ((va hanh) OR (va danh)) vi cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang cau hoi. lieu ((va cao) OR (va dao)) suc ((va hanh) or (va danh)) vi cau tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cau hoi. lieu ((va cao) OR (va dao)) suc ((va hanh) or (va danh)) vi cau tren*.