Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
lam tuc » lam thuoc, lam truoc, luat tuc
cua tre » cua te, cuu tre, cua triet
hieu va » hieu qua
ty nang » ky nang, ty hang, ly nang
tuc va » thuc va, truc va, tuc xa
va cua » va chua, via cua, 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 ((ty nang) OR (ty xang)) xa hoi. ((hieu va) or (lieu va)) lam tuc va tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty xang)) xa hoi. ((hieu va) OR (lieu va)) lam tuc va tinh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) OR (ty xang)) xa hoi. ((hieu va) or (lieu va)) lam tuc va tinh va cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) OR (ty xang)) xa hoi. ((hieu va) or (lieu va)) lam tuc va tinh va cua tre*.