Perhaps you should try some spelling variations:
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
cau thuc » cau truc, cuu thuc, can thuc
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ve cau » ke cau, va cau, ve cac
de cua » le cua, te cua, dieu cua
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: su sach van nang x hoi. hieu ve cau thuc ((van hanh) OR (ban hanh)) de cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach van nang x hoi. hieu ve cau thuc ((van hanh) OR (ban hanh)) de cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach van nang x hoi. hieu ve cau thuc ((van hanh) OR (ban hanh)) de cua tre*.