Perhaps you should try some spelling variations:
thanh va » thanh van, hanh va, thanh ha
cau tren » cu tren, dau tren, ca tren
te sach » toc sach
sach ky » sac ky, sach y, sach ty
van bao » van dao
duc van » duc va, duc manh, duc phan
va cau » van cau, va cac, va dau
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 ky nang x hoi. hieu ((van bao) OR (van ban)) ((duc van) or (duc tan)) thanh va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang x hoi. hieu ((van bao) OR (van ban)) ((duc van) OR (duc tan)) thanh va cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang x hoi. hieu ((van bao) OR (van ban)) ((duc van) or (duc tan)) thanh va cau tren".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang x hoi. hieu ((van bao) OR (van ban)) ((duc van) or (duc tan)) thanh va cau tren*.