Perhaps you should try some spelling variations:
doanh vien » doanh tien, doanh chien, thanh vien
thuc dayt » thuc vat, thuc dan, thuc xay
thuc day » thuc dan, thuc vat
vien cac » vien bach, vien dai, vien da
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
qua cai » qua hai, qua cac, qua ca

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 tang xa hoi. hieu qua cai ((thuc dayt) or (thuc day)) doanh vien cac tro~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang xa hoi. hieu qua cai ((thuc dayt) OR (thuc day)) doanh vien cac tro.
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang xa hoi. hieu qua cai ((thuc dayt) or (thuc day)) doanh vien cac tro*.