Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
dua tren » dung tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va danh » va dinh, va dan, va hanh
va anh » van anh, va hanh, va banh
cua te » cua tu

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 ky nang xa hoi. hieu van nam thuc ((va anh) or (va danh)) dai ((dua tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu van nam thuc ((va anh) OR (va danh)) dai ((dua tren) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu van nam thuc ((va anh) or (va danh)) dai ((dua tren) or (cua te))*.