Perhaps you should try some spelling variations:
duc tien » duc thien, luc tieng, thuc tien
thu sach » thuat sach, thuoc sach, thu hoach
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
dang mau » dong mau, dang van, dang su
tai duc » tai cuc, mai duc, tai du
xuc van » duc van, luc van, vuc van
tu sach » su sach, te sach, tu cach
mau hoa » cau hoa, ma hoa, mai hoa
ky dang » ky nang, ky danh
ve 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) OR (thu sach)) ky dang mau hoa. hieu ((ve cac) or (va cac)) xuc van hanh tai duc tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky dang mau hoa. hieu ((ve cac) OR (va cac)) xuc van hanh tai duc tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky dang mau hoa. hieu ((ve cac) or (va cac)) xuc van hanh tai duc tien".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky dang mau hoa. hieu ((ve cac) or (va cac)) xuc van hanh tai duc tien*.