Perhaps you should try some spelling variations:
sinh khoan » sinh khoa, sinh hoat, dinh khoa
trung sinh » truong sinh, trong sinh, trung binh
khoan phai » khong phai, khoa phau, khoan hoi
phai thong » phap thong, phai tuong, phan thong
hoc thong » hoc thuong, hoc trong, hoc hong
truoc cac » truoc cach, truoc cang, truoc cuoc
xa truoc » xa truong, lam truoc, nam truoc
cac khoa » cac khoan, cac khoi, dac khoa
khoa hoc » hoa hoc
ba trung » tai trung, nam trung, do trung
te sach » toc sach
sach xa » sach dao, sach nha, sach bai
sach ba » sach bai, sach bac, sach bao

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 xa truoc cac khoa hoc thong ) or ( te sach ba trung sinh khoan phai thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach xa truoc cac khoa hoc thong ) OR ( te sach ba trung sinh khoan phai thong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach xa truoc cac khoa hoc thong ) or ( te sach ba trung sinh khoan phai thong ))*.