Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van chat » cao chat
danh dai » danh dau, danh di, danh sai
cua viet » ca viet, cua vat, cua dieu
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
soc va » hoc va, loc va, goc va
doc va » duoc va, hoc va, duc 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 ky nang xa hoi. hieu van chat ((soc va) or (doc va)) danh dai ((cua viet) OR (hoa viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang xa hoi. hieu van chat ((soc va) OR (doc va)) danh dai ((cua viet) OR (hoa viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang xa hoi. hieu van chat ((soc va) or (doc va)) danh dai ((cua viet) OR (hoa viet))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. hieu van chat ((soc va) or (doc va)) danh dai ((cua viet) OR (hoa viet))*.