Perhaps you should try some spelling variations:
bieu thien » bieu hien, dieu khien, bien phien
khoan phai » khong phai, khoa phau, khoan hoi
phai thong » phap thong, phai tuong, phan thong
tren thuoc » trien thuoc, tren thuc, trung thuoc
thuoc sach » hoc sach, nuoc sach, thuat sach
cach bieu » cach bien, cach tieu, cac bieu
thien cac » hien cac, thien cau, thieu cac
sach tren » sach tien, sach tranh
sach khoa » bach khoa, sach nha, anh khoa
pho thong » he thong
thu sach » tu sach, thuat sach, thu hoach
khoa pho » khoa phu, khoa khoa, khoa phau
vu cach » va cach, ve cach, vu bach

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( vu cach bieu thien cac khoan phai thong ) or ( thu sach tren thuoc sach khoa pho thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( vu cach bieu thien cac khoan phai thong ) OR ( thu sach tren thuoc sach khoa pho thong )).
• Adding a wildcard symbol may retrieve word variants: (( vu cach bieu thien cac khoan phai thong ) or ( thu sach tren thuoc sach khoa pho thong ))*.