Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
dai hoi » dai hoc, dai hai, dai moi
da nang » cam nang, kha nang, cao nang
vu nang » vuc nang, va nang, vu dang
su tien » su kien, su hien, tu tieng
va cam » va cham, va cac, va cao
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((vu nang) or (da nang)) dai hoi. hieu va cam xuc ((van hanh) OR (van thanh)) ki su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((vu nang) OR (da nang)) dai hoi. hieu va cam xuc ((van hanh) OR (van thanh)) ki su tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((vu nang) or (da nang)) dai hoi. hieu va cam xuc ((van hanh) OR (van thanh)) ki su tien".
• Adding a wildcard symbol may retrieve word variants: tu sach ((vu nang) or (da nang)) dai hoi. hieu va cam xuc ((van hanh) OR (van thanh)) ki su tien*.