Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
van dinh » van minh, van dich, va dinh
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 va » lieu va, hieu qua
chat xu » chat xuc, chao xu, chat huu
va tinh » may tinh
va cua » va chua, via cua, ca cua
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: tu sach ky nang xa hoi. ((hieu van) OR (hieu va)) chat xu ((va tinh) or (van dinh)) va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu van) OR (hieu va)) chat xu ((va tinh) OR (van dinh)) va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. ((hieu van) OR (hieu va)) chat xu ((va tinh) or (van dinh)) va cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu van) OR (hieu va)) chat xu ((va tinh) or (van dinh)) va cua te*.