Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
va danh » va dinh, va dan, va hanh
cho cua » co cua, chi cua, cho cu
y nang » ky nang, ly nang, v nang
me hoi » le hoi
tru va » truc va, tu va, trung va
cho ca » cho cac, cho can, cho cay
va ca » va cac, va cao, va cai

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 y nang ((me hoi) or (ma hoa)). hieu va ca tru va danh ((cho cua) OR (cho ca)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((me hoi) OR (ma hoa)). hieu va ca tru va danh ((cho cua) OR (cho ca)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ((me hoi) or (ma hoa)). hieu va ca tru va danh ((cho cua) OR (cho ca)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((me hoi) or (ma hoa)). hieu va ca tru va danh ((cho cua) OR (cho ca)) tre*.