Perhaps you should try some spelling variations:
khoan khau » khoanh khac, khoa kham, khoa phau
khan thong » khap thong, nhan thong, phan thong
khau thong » khau thuong, khap thong, khau tong
sach tien » sach tren, sach thieu
tien thuc » trien thuc, kien thuc, bien thuc
thuc cac » thuc cach, tuc cac, phuc cac
kho khan » khoa kham, khoa than
thu sach » tu sach, thuat sach, thuoc sach
sach tri » sach tai, sach tren, sach truc
tri thuc » tri tue
te sach » toc sach
cac kho » cac khoi, cac khoa, cac khu

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 tien thuc cac kho khan thong ) or ( thu sach tri thuc cac khoan khau thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach tien thuc cac kho khan thong ) OR ( thu sach tri thuc cac khoan khau thong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach tien thuc cac kho khan thong ) or ( thu sach tri thuc cac khoan khau thong ))*.