Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
tang xa » trang xa, tang ma, lang xa
qua cau » quan cau, qua cac, qua ca
cau duc » cao duc, cau luc, chu duc
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
y tang » ky tang, 6 tang, 7 tang
de cua » le cua, te cua, dieu cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y tang xa hoi. hieu qua cau duc va hanh ((de cua) or (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y tang xa hoi. hieu qua cau duc va hanh ((de cua) OR (vai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: so sach y tang xa hoi. hieu qua cau duc va hanh ((de cua) or (vai cua)) tre*.