Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, tu cach
te sach » toc sach
nang xa » nang x, lang xa, nang ma
qua cam » qua cham, qua cac, qua ca
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
su tien » su hien, tu tieng, dau tien
kien » bien, vien, dien

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 (te sach)) ky nang xa hoi. hieu qua cam duc van hanh tai ((su tien) or (su kien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky nang xa hoi. hieu qua cam duc van hanh tai ((su tien) OR (su kien)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky nang xa hoi. hieu qua cam duc van hanh tai ((su tien) or (su kien))*.