Perhaps you should try some spelling variations:
lang van » dang van, tang van, hoang van
thanh vi » thanh va, thanh ve, nhanh vi
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cac hoc » cach hoc, cac hop, bac hoc
cua tre » cua te, cuu tre, cua triet
te sai » te tai, te bai, te lai
sai ky » sac ky

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 xa) or (lang van)) hoi. hieu va cac hoc va ((thanh vi) OR (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sai ky ((nang xa) OR (lang van)) hoi. hieu va cac hoc va ((thanh vi) OR (hanh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sai ky ((nang xa) or (lang van)) hoi. hieu va cac hoc va ((thanh vi) OR (hanh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: te sai ky ((nang xa) or (lang van)) hoi. hieu va cac hoc va ((thanh vi) OR (hanh vi)) cua tre*.