Perhaps you should try some spelling variations:
thuc dan » thuc hanh, thuc vat
so sach » so sanh, bo sach, co sach
sach xu » sach xa, cach xu, mach xu
xu dang » su dang, vu dang, xo dang
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va, hieu qua
va pham » van pham, va phat, va phap
hai cua » thai cua, hoi cua, lai 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 xu dang xa hoi. hieu va pham ((thuc dan) or (hoc dan)) hanh ((hai cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach xu dang xa hoi. hieu va pham ((thuc dan) OR (hoc dan)) hanh ((hai cua) OR (dai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: so sach xu dang xa hoi. hieu va pham ((thuc dan) or (hoc dan)) hanh ((hai cua) or (dai cua)) tre*.