Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dinh dao » dinh dat, minh dao, dinh cao
su triet » su viet, su tien, ve triet
thien va » thien van, tien va, thien tai
va cham » va chat, va tham
truc va » thuc vat, trung va
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang x hoi. thien va cham ((truc va) OR (thuc va)) dinh dao ((cua tre) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang x hoi. thien va cham ((truc va) OR (thuc va)) dinh dao ((cua tre) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang x hoi. thien va cham ((truc va) OR (thuc va)) dinh dao ((cua tre) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang x hoi. thien va cham ((truc va) OR (thuc va)) dinh dao ((cua tre) or (su triet))*.