Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
cua viet » ca viet, hoa viet, cua vat
hanh vai » hanh vi, hanh va, hanh tai
ban hanh » ban hang
cap nuoc » dat nuoc
cac nuoc » hoc nuoc, dat nuoc, cua nuoc
sach ty » sach y, sach tu, sach thu
nang ma » tang ma, sang ma, nang cao
vai cua » dai cua, hai cua, lai cua
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sac ky)) nang ma hoi. hieu viec ((cac nuoc) OR (cap nuoc)) ban hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sac ky)) nang ma hoi. hieu viec ((cac nuoc) OR (cap nuoc)) ban hanh vai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sac ky)) nang ma hoi. hieu viec ((cac nuoc) OR (cap nuoc)) ban hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sac ky)) nang ma hoi. hieu viec ((cac nuoc) OR (cap nuoc)) ban hanh vai cua viet*.