Perhaps you should try some spelling variations:
dang xay » dang van, van xay
van hanh » van thanh, ban hanh, van anh
hanh dai » hanh tai, hanh dao, vanh dai
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, lang van
qua cac » cua cac
cac hoc » cach hoc, cac hop, bac hoc
hoc van » hoc dan, hoc va, hoc vat
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 (((lang xa) or (dang xay)))) hoi. hieu qua cac hoc van hanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky ((nang xa) OR (((lang xa) OR (dang xay)))) hoi. hieu qua cac hoc van hanh dai cua te.
• Adding a wildcard symbol may retrieve word variants: te sac ky ((nang xa) or (((lang xa) or (dang xay)))) hoi. hieu qua cac hoc van hanh dai cua te*.