Perhaps you should try some spelling variations:
sang mai » sang ma, sang tai, lang mai
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
dan cua » ban cua, dai cua, day cua
cam luc » cam xuc, cau luc
hieu va » lieu va, hieu qua
hieu ve » hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
luc va » duc va, tuc va, loc va

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 ky sang mai hoi. ((hieu ve) or (hieu va)) cam luc va thanh ((dan cua) OR (dan ca)) vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky sang mai hoi. ((hieu ve) OR (hieu va)) cam luc va thanh ((dan cua) OR (dan ca)) vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky sang mai hoi. ((hieu ve) or (hieu va)) cam luc va thanh ((dan cua) OR (dan ca)) vat".
• Adding a wildcard symbol may retrieve word variants: tu sach ky sang mai hoi. ((hieu ve) or (hieu va)) cam luc va thanh ((dan cua) OR (dan ca)) vat*.