Perhaps you should try some spelling variations:
dan manh » dang manh, doan manh, van manh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
va viet » hoa viet, san viet, mai viet
ve nam » he nam, va nam, te nam
le nam » ly nam, he nam, le na
vai va » mai va, dai va, hai va
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 ky nang x hoi. hieu ((ve nam) OR (le nam)) thuc ((dan manh) or (hoang minh)) vai va viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. hieu ((ve nam) OR (le nam)) thuc ((dan manh) OR (hoang minh)) vai va viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. hieu ((ve nam) OR (le nam)) thuc ((dan manh) or (hoang minh)) vai va viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu ((ve nam) OR (le nam)) thuc ((dan manh) or (hoang minh)) vai va viet*.