Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thu sach » thuat sach, thuoc sach, thu hoach
thanh va » thanh van, hanh va, thanh ha
va trien » va truyen, va thiet, va tuyen
tu sach » su sach, te sach, tu cach
cao hoc » co hoc, cho hoc, chat hoc
cam duc » cao duc, pham duc, nam duoc
y nang » ky nang, ly nang, v nang
va va » va van, va vua, va vai

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)) y nang cao hoc. hieu qua ((cam duc) OR (cam xuc)) ban thanh va va trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y nang cao hoc. hieu qua ((cam duc) OR (cam xuc)) ban thanh va va trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) y nang cao hoc. hieu qua ((cam duc) OR (cam xuc)) ban thanh va va trien".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) y nang cao hoc. hieu qua ((cam duc) OR (cam xuc)) ban thanh va va trien*.