Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
danh ca » dan ca, doanh cua, danh cho
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
xuc va » tuc va, luc va, xac va
ca cua » co cua

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