Perhaps you should try some spelling variations:
can thuc » dan thuc, van thuc, cay thuc
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
tu sach » thu sach, su sach, te sach
xay hoi » tay hoi, cay phoi, gay thoi
hieu va » lieu va, hieu qua
hanh ca » hanh cac, hanh cat, hanh cua
sach o » sach lo, sac o, sach y
o dang » xo dang, do dang, so dang
va can » va chan, va cac, va cao
ca cua » co cua
cua te » cua tu

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 o dang ((xay hoi) OR (xa hoi)). hieu va can thuc dan hanh ca cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach o dang ((xay hoi) OR (xa hoi)). hieu va can thuc dan hanh ca cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach o dang ((xay hoi) OR (xa hoi)). hieu va can thuc dan hanh ca cua te*.