Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
tuc va » truc va, tuc xa, duc va
va co » vo co
di va » dai va, doi va, di vat

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 va co ((tuc va) OR (thuc va)) xanh ((di va) OR (di vao)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu va co ((tuc va) OR (thuc va)) xanh ((di va) or (di vao)) triet~".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu va co ((tuc va) OR (thuc va)) xanh ((di va) or (di vao)) triet*.