Perhaps you should try some spelling variations:
khoan phap » khoan phai, khoa phau, han phap
phap thong » phap phong, phap chong, pho thong
cach khuan » cach hoan
sach tham » sach nha
tham thuc » nham thuc, pham thuc, tam thuc
thuc cach » thuoc sach, truoc cach, thuc hanh
khuan hoa » khuan khoa, chuan hoa, nhuan khoa
hoa thong » hoa trong, hoa khong, hoa thon
sach tai » sach bai, sach dao, sach xa
tai thac » tai thanh, khai thac, mai thach
thac cac » thoai cac, thanh cac, hoc cac
tu sach » thu sach, su sach, te sach
vu sach » vu bach, su sach, vu khach

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 tai thac cac khoan phap thong ) or ( vu sach tham thuc cach khuan hoa thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tai thac cac khoan phap thong ) OR ( vu sach tham thuc cach khuan hoa thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tai thac cac khoan phap thong ) or ( vu sach tham thuc cach khuan hoa thong ))*.