Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
dang van » hoang van, hang va
va thanh » gia thanh, ban thanh, va tinh
hieu va » lieu va
cac hoc » cach hoc, cac hop, bac hoc
te sai » te tai, te bai, te lai
sai ky » sac ky
cua tu » cua tuc, cua su, cua cu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sai ky ((nang x) or (dang van)) hoi. ((hieu va) or (hieu qua)) cac hoc va thanh dai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sai ky ((nang x) OR (dang van)) hoi. ((hieu va) OR (hieu qua)) cac hoc va thanh dai cua tu.
• Adding a wildcard symbol may retrieve word variants: te sai ky ((nang x) or (dang van)) hoi. ((hieu va) or (hieu qua)) cac hoc va thanh dai cua tu*.