Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
hanh ca » hanh cac, hanh cat, hanh cua
va hanh » van hanh, va thanh, va danh
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
ty nang » ky nang, ty xang, ty hang
cuu tre » cua tre, cau tren, cau treo
ma hoi » xa hoi, ma hoa, me hoi
ca cuu » cap cuu, cua cuu, ca cua

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((ma hoi) OR (mai hoi)). hieu va ((tac tu) OR (cac du)) va hanh ca cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((ma hoi) OR (mai hoi)). hieu va ((tac tu) or (cac du)) va hanh ca cuu tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((ma hoi) OR (mai hoi)). hieu va ((tac tu) or (cac du)) va hanh ca cuu tre*.