Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
ve cham » va cham, ve chat, vu cham
va dan » ca dan, va dau, va dap
va dao » ca dao

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 lang) or (ky dang)) xa hoi. hieu ve cham truc ((va dan) OR (va dao)) dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky dang)) xa hoi. hieu ve cham truc ((va dan) OR (va dao)) dai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) or (ky dang)) xa hoi. hieu ve cham truc ((va dan) OR (va dao)) dai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky dang)) xa hoi. hieu ve cham truc ((va dan) OR (va dao)) dai cua viet*.