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

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu van) OR (lieu va)) cau truc va danh ((vai cua) OR (di cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. ((hieu van) OR (lieu va)) cau truc va danh ((vai cua) or (di cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu van) OR (lieu va)) cau truc va danh ((vai cua) or (di cua)) tre*.