Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
tru nang » tra nang, tri nang, truc nano
hanh dai » hanh tai, hanh dao, vanh dai
va triet » va thiet, va trien, ve triet
tu nang » tu nong, tu nano, tu lang
cao suc » cao su, cao duc
xa hanh » xa thanh, xa khanh, va hanh
va cao » va cac, va co, va dao
suc xa » tuc xa, buc xa, suc ma
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: toc sach ((tu nang) or (tru nang)) xa hoi. lieu va cao suc xa hanh dai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tu nang) OR (tru nang)) xa hoi. lieu va cao suc xa hanh dai va triet.
• Adding a wildcard symbol may retrieve word variants: toc sach ((tu nang) or (tru nang)) xa hoi. lieu va cao suc xa hanh dai va triet*.