Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
van dam » van nam, van dao, van dau
va danh » va dinh, va dan, va hanh
danh va » doanh va, hanh va, anh va
so viet » hoc viet
ma hoi » mai hoi, xa hoi, ma hoa
dam tu » nam tu, cam tu, tam tu

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 ma hoi. hieu van dam tu va danh va ((su viet) or (so viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ma hoi. hieu van dam tu va danh va ((su viet) OR (so viet)).
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ma hoi. hieu van dam tu va danh va ((su viet) or (so viet))*.