Perhaps you should try some spelling variations:
nhung don » nhung van, nhung bo
thu sach » thuat sach, thuoc sach, thu hoach
khoa hoc » hoa hoc
hoc kieu » hoc dieu, hoc sieu, hoc tieu
kieu cao » lieu cao, sieu cao, chieu cao
tu sach » su sach, te sach, tu cach
cao cua » ca cua, co cua, cau cua
don so » dong so, hon so, con so
so vi » so voi, so va, so di

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) or (thu sach)) khoa hoc kieu cao cua ets : nhung don so vi đai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) khoa hoc kieu cao cua ets : nhung don so vi đai.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) khoa hoc kieu cao cua ets : nhung don so vi đai*.