Perhaps you should try some spelling variations:
khan thong » khap thong, nhan thong, phan thong
khau thong » khau thuong, khap thong, khau tong
cach thuc » anh thuc, cac thu
nang khoa » hang khoa, dang khoa, nang hoa
khoa khau » khoa kham, khoa phau, khoa chau
tru cuoc » tru quoc, truoc cuoc, thuc cuoc
cach kho » bach khoa, cach thoi, cach pha
kho khan » khoa kham, khoa than
thuc kha » thuc khoa, thuc khac, thuc ha
kha nang » phap nang, ky nang, ki nang
cac tru » ca tru, cac tro, cac thu
te cach » ve cach, te sach, tu cach

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 tru cuoc cach kho khan thong ) or ( te cach thuc kha nang khoa khau thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu cac tru cuoc cach kho khan thong ) OR ( te cach thuc kha nang khoa khau thong )).
• Adding a wildcard symbol may retrieve word variants: (( tu cac tru cuoc cach kho khan thong ) or ( te cach thuc kha nang khoa khau thong ))*.