Perhaps you should try some spelling variations:
duc tien » duc thien, luc tieng, thuc tien
va thanh » gia thanh, ban thanh, va tinh
dang mat » dang vat, dang mau, dung mat
ban hanh » ban hang
duc tre » duoc tren
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cac tuc » cac toc, cac tu, cac tac
hieu ve » hieu va, hieu van
mat hoa » ma hoa, mai hoa, chat hoa
ky dang » ky nang, ky danh
ve cac » va cac, vien cac

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 ky dang mat hoa. hieu ve cac tuc ((va thanh) or (ban hanh)) may ((duc tre) OR (duc tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang mat hoa. hieu ve cac tuc ((va thanh) OR (ban hanh)) may ((duc tre) OR (duc tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky dang mat hoa. hieu ve cac tuc ((va thanh) or (ban hanh)) may ((duc tre) OR (duc tien))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang mat hoa. hieu ve cac tuc ((va thanh) or (ban hanh)) may ((duc tre) OR (duc tien))*.