Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
dang xay » dang van, van xay
va thanh » gia thanh, ban thanh, va tinh
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
cac hoc » cach hoc, cac hop, bac hoc
hai cua » thai cua, dai cua, hoi cua
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
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: te sac ky ((((nang xa) OR (nang x))) or (dang xay)) hoi. hieu va cac hoc va thanh hai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky ((((nang xa) OR (nang x))) OR (dang xay)) hoi. hieu va cac hoc va thanh hai cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky ((((nang xa) OR (nang x))) or (dang xay)) hoi. hieu va cac hoc va thanh hai cua te*".