Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
ban thanh » ban hanh, ban hang
toc sach » hoc sach, doc sach, thuoc sach
cam dua » ca dua, chay dua, cach dua
hai cuc » tai cuc, hai cua, thai cua
cay dua » chay dua, cay lua, ca dua
cuc tre » duc tre, cua tre, cuu tre
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ky nang, ty hang, ly nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ty nang) or (ty xang)) mai hoi. hieu ve ((cam dua) OR (cay dua)) ban thanh hai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ty nang) OR (ty xang)) mai hoi. hieu ve ((cam dua) OR (cay dua)) ban thanh hai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((ty nang) or (ty xang)) mai hoi. hieu ve ((cam dua) OR (cay dua)) ban thanh hai cuc tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((ty nang) or (ty xang)) mai hoi. hieu ve ((cam dua) OR (cay dua)) ban thanh hai cuc tre*.