Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
danh dai » danh dau, danh di, danh sai
hieu van » hieu va, thien van, lieu va
van chat » cao chat
nang ma » tang ma, sang ma, nang cao
tu hach » tu hanh, tu cach, tu sach
ma hoi » mai hoi, xa hoi, ma hoa
soc va » hoc va, doc va, goc va
loc va » hoc va, luc va
tu bac » tu ban, tu cac, tu bat

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu bac) or (tu hach)) ky nang ma hoi. hieu van chat ((soc va) OR (loc va)) danh dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu bac) OR (tu hach)) ky nang ma hoi. hieu van chat ((soc va) OR (loc va)) danh dai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu bac) or (tu hach)) ky nang ma hoi. hieu van chat ((soc va) OR (loc va)) danh dai cua viet".
• Adding a wildcard symbol may retrieve word variants: ((tu bac) or (tu hach)) ky nang ma hoi. hieu van chat ((soc va) OR (loc va)) danh dai cua viet*.