Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
dan manh » dang manh, doan manh, van manh
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ca viet » co viet, hoa viet, san viet
va viet » hoa viet, san viet, mai viet
y nang » ky nang, ly nang, v nang
ve nam » he nam, va nam, le nam

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 y nang xa hoi. hieu ve nam thuc ((dan manh) or (hoang minh)) bai ((ca viet) OR (va viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu ve nam thuc ((dan manh) OR (hoang minh)) bai ((ca viet) OR (va viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu ve nam thuc ((dan manh) or (hoang minh)) bai ((ca viet) OR (va viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu ve nam thuc ((dan manh) or (hoang minh)) bai ((ca viet) OR (va viet))*.