Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nang mai » nang ma, nang tai, lang mai
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
va cam » va cham, va cac, va cao
di hoa » dai hoa, doi hoa, do hoa

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) or (thuoc sach)) ky nang mai hoi. hieu va cam xuc ((va danh) OR (va hanh)) di hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky nang mai hoi. hieu va cam xuc ((va danh) OR (va hanh)) di hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuoc sach)) ky nang mai hoi. hieu va cam xuc ((va danh) OR (va hanh)) di hoa viet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky nang mai hoi. hieu va cam xuc ((va danh) OR (va hanh)) di hoa viet*.