Perhaps you should try some spelling variations:
sach chuc » cach thuc, sach che, sach thu
toc sach » hoc sach, doc sach, thuoc sach
hanh lai » hanh lam, hanh tai, thanh lap
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
duc van » duc va, duc manh, duc phan
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach chuc nang xa hoi. hieu va cac ((duc van) or (duc tan)) hanh lai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach chuc nang xa hoi. hieu va cac ((duc van) OR (duc tan)) hanh lai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach chuc nang xa hoi. hieu va cac ((duc van) or (duc tan)) hanh lai ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: toc sach chuc nang xa hoi. hieu va cac ((duc van) or (duc tan)) hanh lai ((cua tre) OR (cua te))*.