Perhaps you should try some spelling variations:
hieu nghe » lieu nghe, hiem ngheo, nhiem nghe
nghe nano » nghe dan, nghe san, nghe nhan
hai cua » thai cua, dai cua, hoi cua
sai cua » dai cua, lai cua, bai cua
va danh » va dinh, va dan, va hanh
nano tu » nang tu, nao tu, nano cau
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, me hoi

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