Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
van thanh » ban thanh, van tuan
tru nang » tra nang, tri nang, truc nano
va triet » va thiet, va trien, ve triet
te sach » toc sach
tu nang » tu nong, tu nano, tu lang
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
dai va » mai va

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

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