Perhaps you should try some spelling variations:
pham cuc » pham chuc, pham duc, pham cua
hieu van » thien van, lieu va, hieu ve
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
ban dan » ban hang, ban hanh, ban quan
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
dan vi » doan vi, don vi, dan va
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 lang) or (ky dang)) xa hoi. ((hieu van) OR (hieu va)) pham cuc ban dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. ((hieu van) OR (hieu va)) pham cuc ban dan vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) or (ky dang)) xa hoi. ((hieu van) OR (hieu va)) pham cuc ban dan vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky dang)) xa hoi. ((hieu van) OR (hieu va)) pham cuc ban dan vi cua tre*.