Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van ban
sach thu » sach thue, sach thieu, sach tham
van anh » van thanh, tuan anh, van minh
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
sach ty » sach y, sach tu, xach tay
ve cau » ke cau, va cau, ve cac
le cua » ly 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: te ((sach ty) OR (sach thu)) nang x hoi. hieu ve cau truc ((van hanh) or (van anh)) le cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach thu)) nang x hoi. hieu ve cau truc ((van hanh) OR (van anh)) le cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) OR (sach thu)) nang x hoi. hieu ve cau truc ((van hanh) or (van anh)) le cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) OR (sach thu)) nang x hoi. hieu ve cau truc ((van hanh) or (van anh)) le cua tre*.