Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cau » van dau, van hau, van chat
truc va » thuc va, thuc vat, trung va
va danh » va dinh, va dan, va hanh
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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 cau truc va danh ((vi cua) or (di cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu van cau truc va danh ((vi cua) OR (di cua)) tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu van cau truc va danh ((vi cua) or (di cua)) tre*.