Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cau theo » cau thi
ban hanh » ban hang
quoc ban » quoc bao, quoc lan, quoc quan
tru nang » tra nang, tri nang, truc nano
cam quoc » cac quoc, cao quoc, nam quoc
van cam » van nam, van lam, van cau
te sach » toc sach
tu lang » cu lang, tu lanh, xu lang

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 lang) or (tru nang)) xa hoi. hieu van cam quoc ban hanh vi ((cau theo) OR (cau tao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu lang) OR (tru nang)) xa hoi. hieu van cam quoc ban hanh vi ((cau theo) OR (cau tao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu lang) or (tru nang)) xa hoi. hieu van cam quoc ban hanh vi ((cau theo) OR (cau tao))".
• Adding a wildcard symbol may retrieve word variants: te sach ((tu lang) or (tru nang)) xa hoi. hieu van cam quoc ban hanh vi ((cau theo) OR (cau tao))*.