Perhaps you should try some spelling variations:
manh vai » manh hai, manh va, manh khai
thu sach » thuat sach, thuoc sach, thu hoach
thuc dan » thuc hanh, hoc dan
tu sach » su sach, te sach, tu cach
ca viet » va viet, co viet, hoa viet
hieu ve » hieu va, hieu van
vai ca » vai cac, vai cua, bai ca
ve nam » he nam, va nam, le nam
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: ((tu sach) OR (thu sach)) ky nang x hoi. hieu ve nam ((thuc dan) or (thuc vat)) manh vai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang x hoi. hieu ve nam ((thuc dan) OR (thuc vat)) manh vai ca viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang x hoi. hieu ve nam ((thuc dan) or (thuc vat)) manh vai ca viet*".