Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
mai khoi » mai khoa, tai khoa, cac khoi
danh vai » danh sai, danh va, doanh van
cham xuc » chat xuc, cham soc, pham duc
dau tren » dau tien, dat tren, dau tieng
hieu ve » hieu va, hieu van
mai hoi » dai hoi, lai hoi, mai doi
va danh » va dinh, va dan, va hanh
vai dau » va dau, van dau, xvii dau
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y nang ((mai hoi) or (mai khoi)). hieu ve ((cham xuc) OR (cam xuc)) va danh vai dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang ((mai hoi) OR (mai khoi)). hieu ve ((cham xuc) OR (cam xuc)) va danh vai dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang ((mai hoi) or (mai khoi)). hieu ve ((cham xuc) OR (cam xuc)) va danh vai dau tren".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang ((mai hoi) or (mai khoi)). hieu ve ((cham xuc) OR (cam xuc)) va danh vai dau tren*.