Perhaps you should try some spelling variations:
sach ky » sac ky, sach y, sach ty
bac cau » bach cau, ba cau, bac can
cac cau » cac mau, ca cau, cac cam
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
cam tuc » cam xuc, cam tu, nam thuc
cao hoi » cau hoi, co hoi, cao hoc
va dap » va dao, va dau
ca dan » cac dan, ca dao
ve cam » ve cham, ve cac, va cam

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 cao hoi. hieu ve cam tuc ((va dap) or (ca dan)) ((cac cau) or (bac cau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang cao hoi. hieu ve cam tuc ((va dap) OR (ca dan)) ((cac cau) OR (bac cau)) tren.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang cao hoi. hieu ve cam tuc ((va dap) or (ca dan)) ((cac cau) or (bac cau)) tren*.