Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
vai cua » dai cua, hai cua, lai cua
cac duc » cac du, cao duc, cac dac
tu nano » truc nano
tu nang » tru nang, tu nong, tu lang
cua tu » cua tuc, cua su, cua cu

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 (tu nano)) xa hoi. hieu van ((cac duc) or (giao duc)) van hanh vai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (tu nano)) xa hoi. hieu van ((cac duc) OR (giao duc)) van hanh vai cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu nang) OR (tu nano)) xa hoi. hieu van ((cac duc) or (giao duc)) van hanh vai cua tu*".