Perhaps you should try some spelling variations:
kham thong » khap thong, khau thong, pham thuong
hoach tren » hoach trong, hoach toan, hoc tren
tren thuc » trien thuc, tron thuc, trinh thuc
thuc cach » thuoc sach, truoc cach, thuc hanh
cach khoa » bach khoa, cac khoa, cac khoan
pho thong » he thong
khoi kham » khoa kham, kho khan, hoi cham
khoa pho » khoa phu, khoa khoa, khoa phau
sach dao » lanh dao
dao thac » dao thai, dao thanh, cao thach
thac cac » thoai cac, thanh cac, hoc cac
cac khoi » cac thoi, cac khoan, cach thoi
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( thu hoach tren thuc cach khoa pho thong ) or ( tu sach dao thac cac khoi kham thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thu hoach tren thuc cach khoa pho thong ) OR ( tu sach dao thac cac khoi kham thong )).
• Adding a wildcard symbol may retrieve word variants: (( thu hoach tren thuc cach khoa pho thong ) or ( tu sach dao thac cac khoi kham thong ))*.