Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, nam thu, nam tu
vat hanh » vat thanh, van hanh, va hanh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau tren, cau treo
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

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 nang x hoi. hieu van ((nam thuc) OR (am thuc)) vat hanh vi cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. hieu van ((nam thuc) OR (am thuc)) vat hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu van ((nam thuc) OR (am thuc)) vat hanh vi cuu tre*.