Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban thanh » ban hanh, ban hang
thanh va » thanh van, hanh va, thanh ha
hieu van » hieu va, thien van, lieu va
cac dac » cac dan, cac dai, cac bac
te sach » toc sach
ky lang » ky dang, ky tang, tay lang
cac duc » cac du, cao duc, cac nuoc
va cua » va chua, via cua, ca cua

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