Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
hieu ve » hieu van
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
duc van » duc va, duc tan, duc manh
van anh » van thanh, tuan anh, van minh
tu sach » thu sach, su sach, te sach
ve cau » ke cau, ve cac, le cau
va cau » van cau, va cac, va dau

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 ho. ((hieu ve) or (hieu va)) cham duc van anh ((ve cau) OR (va cau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x ho. ((hieu ve) OR (hieu va)) cham duc van anh ((ve cau) OR (va cau)) tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x ho. ((hieu ve) or (hieu va)) cham duc van anh ((ve cau) OR (va cau)) tren".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x ho. ((hieu ve) or (hieu va)) cham duc van anh ((ve cau) OR (va cau)) tren*.