Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hoc sach » hoc sinh, hoc cac, hoc anh
dieu cua » dieu tra
hang ca » hang va, nang cao, hang tai
sach ty » sach y, sach tu, sach thu
hang xa » hoang xa, hang va, lang xa
ca viet » va viet, co viet, hoa viet
lao va » tao va, bao va, dao va
cao va » cao van, tao va, co va
tai ca » tai cac, tai cao, tai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ty ((hang xa) OR (hang ca)) hoi. dieu cua cac ((lao va) or (cao va)) thanh tai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty ((hang xa) OR (hang ca)) hoi. dieu cua cac ((lao va) OR (cao va)) thanh tai ca viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ty ((hang xa) OR (hang ca)) hoi. dieu cua cac ((lao va) or (cao va)) thanh tai ca viet".
• Adding a wildcard symbol may retrieve word variants: hoc sach ty ((hang xa) OR (hang ca)) hoi. dieu cua cac ((lao va) or (cao va)) thanh tai ca viet*.