Perhaps you should try some spelling variations:
phap thuc » phap thu, phap hoc, phap tu
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
va phap » va phat, ban phap
hieu va » lieu va, hieu qua
cao hoi » cau hoi, co hoi, cao hoc
va dap » va dao, va dau
ca dan » cac dan, ca dao
vai va » mai va, dai va, hai va
thiet » thieu

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 cao hoi. hieu va phap thuc ((va dap) or (ca dan)) vai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang cao hoi. hieu va phap thuc ((va dap) OR (ca dan)) vai va thiet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang cao hoi. hieu va phap thuc ((va dap) or (ca dan)) vai va thiet*.