Perhaps you should try some spelling variations:
tren thuoc » trien thuoc, tren thuc, trung thuoc
kham thong » khap thong, khau thong, pham thuong
thuoc sach » hoc sach, nuoc sach, thuat sach
hoach dat » hoach xay, hoc dat, hoach va
cach thoi » cac thoi, cach thuc, cach noi
thoi kham » thoi khac, khoa kham, hoi cham
sach tren » sach tien, sach tranh
sach khoa » bach khoa, sach nha, anh khoa
pho thong » he thong
hoc cach » hoc cac, hoc sach, cuoc cach
khoa pho » khoa phu, khoa khoa, khoa phau
dat hoc » dai hoc, vat hoc, dan hoc
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 dat hoc cach thoi kham thong ) or ( tu sach tren thuoc sach khoa pho thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( thu hoach dat hoc cach thoi kham thong ) OR ( tu sach tren thuoc sach khoa pho thong )).
• Adding a wildcard symbol may retrieve word variants: (( thu hoach dat hoc cach thoi kham thong ) or ( tu sach tren thuoc sach khoa pho thong ))*.