Perhaps you should try some spelling variations:
sanh trong » sinh trong, anh trong, hanh trong
khan thong » khap thong, khau thong, nhan thong
trong thuc » trong thu, thuong thuc, trong thuat
chat thong » chat chong, chat phong, chat trong
sach truc » cach thuc, sach tren, sach thu
thuc cach » thuoc sach, truoc cach, thuc hanh
truc tue » truc tu, truc tuyen, truc tiep
kho khan » khoa kham, khoa than
cach hoc » cach thuc, cach thoi, dich hoc
hoc chat » hoc phat, hoc cao, hoc phan
te sach » toc sach
tue cac » tu cac, tuc cac, te cac
cac kho » cac khoi, cac khoa, cac khu
te sanh » te danh, te san, te doanh

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 truc tue cac kho khan thong ) or ( te sanh trong thuc cach hoc chat thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach truc tue cac kho khan thong ) OR ( te sanh trong thuc cach hoc chat thong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach truc tue cac kho khan thong ) or ( te sanh trong thuc cach hoc chat thong ))*.