Perhaps you should try some spelling variations:
lanh dai » lanh dao, lanh hai, lang dai
tu sach » thu sach, su sach, tu cach
te sach » toc sach
ky sang » ky nang, ky dang, ky tang
sang ma » tang ma, nang ma, sang tao
hieu va » lieu va, hieu qua
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cac, va cao
xuc va » tuc va, luc va, xac 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) or (te sach)) ky sang ma hoi. hieu va cam ((xuc va) OR (duc va)) lanh dai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky sang ma hoi. hieu va cam ((xuc va) OR (duc va)) lanh dai cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ky sang ma hoi. hieu va cam ((xuc va) OR (duc va)) lanh dai cua vat".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky sang ma hoi. hieu va cam ((xuc va) OR (duc va)) lanh dai cua vat*.