Perhaps you should try some spelling variations:
khan thong » khap thong, khau thong, nhan thong
thuc cach » thuoc sach, truoc cach, thuc hanh
phu thong » pho thong, phap thong, khau thong
tro thuc » tron thuc, tra thuc, trong thuc
pha khan » pham khanh, phap khang, phap phan
sach tri » sach tai, sach tren, sach truc
tri thuc » tri tue
thuc cac » tuc cac, phuc cac, thac cac
cac khoa » cac khoan, cac khoi, dac khoa
khoa phu » khoa phau, khoa thu, hoa phu
so sach » so sanh, bo sach, co sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu cac tro thuc cach pha khan thong ) or ( so sach tri thuc cac khoa phu thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cac tro thuc cach pha khan thong ) OR ( so sach tri thuc cac khoa phu thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu cac tro thuc cach pha khan thong ) or ( so sach tri thuc cac khoa phu thong ))*.