Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cau duc » cao duc, cau luc, chu duc
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di 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 ky nang xa hoi. ((((hieu ve) or (hieu quan))) or (hieu qua)) cau duc va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((((hieu ve) OR (hieu quan))) OR (hieu qua)) cau duc va danh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((((hieu ve) or (hieu quan))) or (hieu qua)) cau duc va danh vi cua tre*.