Perhaps you should try some spelling variations:
vu sach » vu bach, su sach, vu khach
nang ma » tang ma, sang ma, nang cao
qua cam » qua cham, qua cac, qua ca
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
vi cua » vai cua, di cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) or (do sanh)) ky ((nang x) or (nang ma)) hoi. hieu qua cam duc va dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (do sanh)) ky ((nang x) OR (nang ma)) hoi. hieu qua cam duc va dan vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (do sanh)) ky ((nang x) or (nang ma)) hoi. hieu qua cam duc va dan vi cua tre*.