Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
van thanh » ban thanh, van tuan
hieu van » hieu va, thien van, lieu va
tang mai » tang ma, tang tai, lang mai
nam thuc » nam thuoc, am thuc, nam thu
nam xuc » cam xuc, nam xua, nam duoc
hai cua » thai cua, dai cua, hoi cua
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
ky tang » ky nang, ky dang, kho tang
vu sach » vu bach, su sach, vu khach
cua tu » cua tuc, cua su, cua cu

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 (vu sach)) ky tang mai hoi. hieu van ((nam xuc) OR (nam thuc)) van thanh hai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) ky tang mai hoi. hieu van ((nam xuc) OR (nam thuc)) van thanh hai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (vu sach)) ky tang mai hoi. hieu van ((nam xuc) OR (nam thuc)) van thanh hai cua tu".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ky tang mai hoi. hieu van ((nam xuc) OR (nam thuc)) van thanh hai cua tu*.