Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thu sach » tu sach, thuoc sach, thu hoach
nang mai » nang ma, nang tai, lang mai
hanh vai » hanh vi, hanh va, hanh tai
ty nang » ky nang, ty xang, ty hang
mai hoi » mai khoi, dai hoi, lai hoi
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
xuc va » duc va, tuc va, luc va

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) OR (thuat sach)) ty nang mai hoi. hieu ((va cac) or (va bai)) xuc va hanh vai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) ty nang mai hoi. hieu ((va cac) OR (va bai)) xuc va hanh vai cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) ty nang mai hoi. hieu ((va cac) or (va bai)) xuc va hanh vai cua vat".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) ty nang mai hoi. hieu ((va cac) or (va bai)) xuc va hanh vai cua vat*.