Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
dua tren » dung tren
thanh vi » hanh vi, thanh va, thanh ve
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
lo van » le van, vo van, so van
cam lo » nam lo, cam ly, cam o
cua te » cua tu
co ky » cao ky, cho ky, do ky
so ky » so ly

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((co ky) OR (so ky)) nang xa hoi. hieu va cam lo van thanh vi ((dua tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((co ky) OR (so ky)) nang xa hoi. hieu va cam lo van thanh vi ((dua tren) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((co ky) OR (so ky)) nang xa hoi. hieu va cam lo van thanh vi ((dua tren) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: thuat ((co ky) OR (so ky)) nang xa hoi. hieu va cam lo van thanh vi ((dua tren) or (cua te))*.