Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hanh ca » hanh cac, hanh cat, hanh cua
qua cac » cua cac
ly nang » ky nang, ly hang, ly vang
cuu tre » cua tre, cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa
y nang » ky nang, v nang, may nang
tac va » tac xa, tuc va, tac ha
ca cuu » cap cuu, cua cuu, ca 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 ((y nang) OR (ly nang)) ma hoi. hieu qua cac ((tac va) or (tac da)) hanh ca cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (ly nang)) ma hoi. hieu qua cac ((tac va) OR (tac da)) hanh ca cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (ly nang)) ma hoi. hieu qua cac ((tac va) or (tac da)) hanh ca cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (ly nang)) ma hoi. hieu qua cac ((tac va) or (tac da)) hanh ca cuu tre*.