Perhaps you should try some spelling variations:
khan thong » khap thong, khau thong, nhan thong
khong phan » thong phan, khong phai, khong phap
phan hong » phan cong, pham hong, phan song
tranh vu » tran vu, tranh va, tranh cua
benh kho » benh phoi, benh hoc, benh lao
kho khan » khoa kham, khoa than
can tran » can tranh, tan tran, ban tran
thi benh » tai benh, tri benh, thi binh
ve canh » van canh, ve thanh
vu benh » va benh, vu binh, cua benh
su can » su van, su cao, tu can

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( ve canh tranh vu benh kho khan thong ) or ( su can tran thi benh khong phan hong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ve canh tranh vu benh kho khan thong ) OR ( su can tran thi benh khong phan hong )).
• Adding a wildcard symbol may retrieve word variants: (( ve canh tranh vu benh kho khan thong ) or ( su can tran thi benh khong phan hong ))*.