Perhaps you should try some spelling variations:
thai khien » thai phien, thai nghien, hai kien
thu nghiep » thu nghiem, chu nghiep, thuat nghiep
cach thai » cach thoi, sach tham, lich thai
sach thu » sach thue, sach thieu, sach tham
giao hoc » gio hoc, giao khoa, giao duc
khien va » thien va, kien va, nhien va
te sach » toc sach
tu cach » tu cac
va hoc » van hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach thu nghiep giao hoc ) or ( tu cach thai khien va hoc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach thu nghiep giao hoc ) OR ( tu cach thai khien va hoc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach thu nghiep giao hoc ) or ( tu cach thai khien va hoc ))*.